Method of manufacturing semiconductor device and substrate processing method

ABSTRACT

A method of manufacturing a semiconductor device for forming a thin film having low permittivity, high etching resistance and high leak resistance is provided. The method includes: forming a film containing a predetermined element, oxygen, carbon and nitrogen on a substrate by performing a cycle a predetermined number of times. The cycle includes: (a) supplying a source gas containing the predetermined element and a halogen element to the substrate; (b) supplying a first reactive gas containing the three elements including carbon, nitrogen and hydrogen wherein a number of carbon atoms in each molecule of the first reactive gas is greater than that of nitrogen atoms in each molecule of the first reactive gas to the substrate; (c) supplying a nitriding gas as a second reactive gas to the substrate; and (d) supplying an oxidizing gas as a third reactive gas to the substrate, wherein (a) through (d) are non-simultaneously performed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/706,221 filed May 7, 2015, entitled “Method Of ManufacturingSemiconductor Device And Substrate Processing Method”, which is acontinuation of U.S. patent application Ser. No. 13/708,966, filed Dec.8, 2012, which claims foreign priority under 35 U.S.C. §119(a)-(d) toJapanese Patent Application No. 2011-270723 filed on Dec. 9, 2011, andJapanese Patent Application No. 2012-233850 filed on Oct. 23, 2012, theentire contents of each of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a method of manufacturing asemiconductor device including a process of forming a thin film on asubstrate, a method of processing a substrate, a substrate processingapparatus and a non-transitory computer readable recording medium.

BACKGROUND

A process of manufacturing a semiconductor device includes a process offorming a silicon-based insulating film such as a silicon oxide film(SiO₂), a silicon nitride film (Si₃N₄), or the like, on a substrate suchas a silicon wafer, i.e., an insulating film containing silicon, whichis a predetermined element. The silicon oxide film is widely used as aninsulating film or an interlayer film having a high insulation propertyand low permittivity. In addition, the silicon nitride film has a goodinsulation property, corrosion resistance, permittivity, film stresscontrollability, or the like, and is widely used as an insulating film,a mask film, a charge accumulation film, or a stress control film.Further, a technique of adding carbon (C) into the insulating film isalso already known, and thus etching resistance of the insulating filmcan be improved.

However, while the etching resistance of the insulating film can beimproved by adding carbon into the insulating film, permittivity may beincreased to deteriorate a leak resistance. That is, while theinsulating films have both merits and demerits, in the related art,there is no thin film having characteristics of low permittivity, highetching resistance, and high leak resistance.

SUMMARY

Accordingly, the present invention is directed to provide a method ofmanufacturing a semiconductor device in which a thin film havingcharacteristics of low permittivity, high etching resistance and highleak resistance can be formed, a method of processing a substrate, asubstrate processing apparatus and a non-transitory computer readablerecording medium.

According to an aspect of the present invention, there is provided amethod of manufacturing a semiconductor device, including: forming afilm containing a predetermined element, oxygen, carbon and nitrogen ona substrate by performing a cycle a predetermined number of times, thecycle including: (a) supplying a source gas containing the predeterminedelement and a halogen element to the substrate; (b) supplying a firstreactive gas containing the three elements including carbon, nitrogenand hydrogen wherein a number of carbon atoms in each molecule of thefirst reactive gas is greater than that of nitrogen atoms in eachmolecule of the first reactive gas to the substrate; (c) supplying anitriding gas as a second reactive gas to the substrate; and (d)supplying an oxidizing gas as a third reactive gas to the substrate,wherein (a) through (d) are non-simultaneously performed.

According to another aspect of the present invention, there is provideda substrate processing method including: forming a film containing apredetermined element, oxygen, carbon and nitrogen on a substrate byperforming a cycle a predetermined number of times, the cycle including:(a) supplying a source gas containing the predetermined element and ahalogen element to the substrate; (b) supplying a first reactive gascontaining three elements including carbon, nitrogen and hydrogenwherein a number of carbon atoms in each molecule of the first reactivegas is greater than that of nitrogen atoms in each molecule of the firstreactive gas to the substrate; (c) supplying a nitriding gas as a secondreactive gas to the substrate; and (d) supplying an oxidizing gas as athird reactive gas to the substrate, wherein (a) through (d) arenon-simultaneously performed.

According to still another aspect of the present invention, there isprovided a method of manufacturing a semiconductor device, including:forming a film containing a predetermined element, oxygen, carbon andnitrogen on a substrate by performing a cycle a predetermined number oftimes, the cycle including: (a) forming a first layer containing thepredetermined element, nitrogen and carbon by alternately performing, apredetermined number of times, supplying a source gas containing thepredetermined element and a halogen element to the substrate; andsupplying a first reactive gas containing three elements includingcarbon, nitrogen and hydrogen wherein a number of carbon atoms in eachmolecule of the first reactive gas is greater than that of nitrogenatoms in each molecule of the first reactive gas to the substrate; (b)nitriding the first layer by supplying a nitriding gas as a secondreactive gas to the substrate; and (c) oxidizing the first layernitrided in (b) by supplying an oxidizing gas as a third reactive gas tothe substrate, wherein the steps (a) through (c) are non-simultaneouslyperformed.

According to yet another aspect of the present invention, there isprovided a non-transitory computer-readable recording medium storing aprogram that causes a computer to perform a process of forming a thinfilm containing a predetermined element on a substrate in a processchamber by performing a cycle a predetermined number of times, the cycleincluding: a process of forming a first layer containing thepredetermined element, nitrogen and carbon by alternately performingsupplying a source gas containing the predetermined element and ahalogen element to the substrate in the process chamber and supplying afirst reactive gas containing three elements including the carbon, thenitrogen and hydrogen and having a composition wherein a number ofcarbon atoms is greater than that of nitrogen atoms to the substrate inthe process chamber a predetermined number of times; and a process offorming a second layer by supplying a second reactive gas different fromthe source gas and the first reactive gas to the substrate in theprocess chamber to modify the first layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a vertical processing furnace of asubstrate processing apparatus exemplarily used in an embodiment of thepresent invention, showing a longitudinal cross-sectional view of aprocessing furnace;

FIG. 2 is a schematic view of the vertical processing furnace of thesubstrate processing apparatus exemplarily used in the embodiment of thepresent invention, showing a cross-sectional view of the processingfurnace taken along line A-A of FIG. 1;

FIG. 3 is a schematic view of a controller of the substrate processingapparatus exemplarily used in the embodiment of the present invention;

FIG. 4 is a view showing a film-forming flow of a first embodiment ofthe present invention;

FIG. 5 is a view showing a gas supply timing in a film-forming sequenceof the first embodiment of the present invention;

FIGS. 6A through 6C are views showing variants of the gas supply timingin the film-forming sequence of the first embodiment of the presentinvention, FIG. 6A showing a variant 1, FIG. 6B showing a variant 2 andFIG. 6C showing a variant 3;

FIG. 7 is a view showing a film-forming flow of a second embodiment ofthe present invention;

FIG. 8 is a view showing a gas supply timing in a film-forming sequenceof the second embodiment of the present invention;

FIGS. 9A through 9C are views showing variants of the gas supply timingof the film-forming sequence of the second embodiment of the presentinvention, FIG. 9A showing a variant 1, FIG. 9B showing a variant 2 andFIG. 9C showing a variant 3;

FIG. 10 is a view showing a film-forming flow of a third embodiment ofthe present invention;

FIG. 11 is a view showing a gas supply timing in a film-forming sequenceof the third embodiment of the present invention;

FIGS. 12A and 12B are views showing variants of the gas supply timing inthe film-forming sequence of the third embodiment of the presentinvention, FIG. 12A showing a variant 1 and FIG. 12B showing a variant2;

FIGS. 13A and 13B are views showing variants of the gas supply timing inthe film-forming sequence of the third embodiment of the presentinvention, FIG. 13A showing a variant 3 and FIG. 13B showing a variant4;

FIGS. 14A and 14B are views showing variants of the gas supply timing inthe film-forming sequence of the third embodiment of the presentinvention, FIG. 14A showing a variant 5 and FIG. 14B showing a variant6;

FIGS. 15A and 15B are views showing variants of a gas supply timing in afilm-forming sequence of another embodiment of the present invention;

FIG. 16 is a view showing various measurement results of a SiOCN of anexample 1 of the present invention;

FIG. 17 is a view showing various measurement results of a SiOC film ofan example 2 of the present invention; and

FIG. 18 is a view showing various measurement results of a SiOCN film ofan example 3 of the present invention.

DETAILED DESCRIPTION First Embodiment of the Invention

Hereinafter, a first embodiment of the present invention will bedescribed with reference to the accompanying drawings.

(1) Configuration of Substrate Processing Apparatus

FIG. 1 is a schematic view of a vertical processing furnace of asubstrate processing apparatus exemplarily used in the embodiment,showing a longitudinal cross-sectional view of a the processing furnace202. FIG. 2 is a schematic view of the vertical processing furnaceexemplarily used in the embodiment, showing a cross-sectional view ofthe processing furnace 202 taken along line A-A of FIG. 1.

As shown in FIG. 1, the processing furnace 202 includes a heater 207,which is a heating unit (a heating mechanism). The heater 207 has acylindrical shape and is supported by a heater base (not shown), whichis a holding plate, to be vertically installed. In addition, the heater207 may function as an activation mechanism (an excitation unit)configured to thermally activate (excite) a gas to be described below.

A reaction tube 203, which is concentric with the heater 207,constituting a reaction vessel (a processing vessel), is installed inthe heater 207. The reaction tube 203 is formed of a heat-resistantmaterial such as quartz (SiO₂) or silicon carbide (SiC), and has acylindrical shape with an upper end closed and a lower end opened. Aprocess chamber 201 is formed in a hollow cylindrical section of thereaction tube 203, and configured to accommodate wafers 200, which aresubstrates, in a state in which the wafers 200 are aligned in a verticaldirection in a horizontal posture in a multi-stage manner by a boat 217.

A first nozzle 249 a, a second nozzle 249 b and a third nozzle 249 c areinstalled in the process chamber 201 to pass through a lower portion ofthe reaction tube 203. A first gas supply pipe 232 a, a second gassupply pipe 232 b and a third gas supply pipe 232 c are connected to thefirst nozzle 249 a, the second nozzle 249 b and the third nozzle 249 c,respectively. In addition, a fourth gas supply pipe 232 d is connectedto the third gas supply pipe 232 c. As described above, the threenozzles 249 a, 249 b and 249 c and the four gas supply pipes 232 a, 232b, 232 c and 232 d are installed at the reaction tube 203 to supply aplurality of kinds, in the embodiment, four kinds, of gases into theprocess chamber 201.

In addition, a manifold formed of metal and configured to support thereaction tube 203 may be installed under the reaction tube 203 such thatthe nozzles pass through a sidewall of the metal manifold. In this case,an exhaust pipe 231 (to be described later) may be installed at themetal manifold. In addition, even in this case, the exhaust pipe 231 maybe installed at a lower portion of the reaction tube 203 rather than atthe metal manifold. As described above, a furnace port of the processingfurnace 202 may be formed of metal, and the nozzles may be installed atthe furnace port formed of metal.

A mass flow controller (MFC) 241 a, which is a flow rate controller (aflow rate control unit), and a valve 243 a, which is an opening/closingvalve, are installed at the first gas supply pipe 232 a in sequence froman upstream direction. In addition, a first inert gas supply pipe 232 eis connected to the first gas supply pipe 232 a at a downstream side ofthe valve 243 a. A mass flow controller 241 e, which is a flow ratecontroller (a flow rate control unit), and a valve 243 e, which is anopening/closing valve, are installed at the first inert gas supply pipe232 e in sequence from the upstream direction. In addition, theabove-mentioned first nozzle 249 a is connected to a front end of thefirst gas supply pipe 232 a. The first nozzle 249 a is installed in anarc-shaped space between an inner wall of the reaction tube 203 and thewafers 200 from a lower portion to an upper portion of the inner wall ofthe reaction tube 203 to rise upward in a stacking direction of thewafers 200. That is, the first nozzle 249 a is installed in a sideregion of a wafer arrangement region, in which the wafers 200 arearranged, horizontally surrounding the wafer arrangement region alongthe wafer arrangement region. The first nozzle 249 a is configured as anL-shaped long nozzle, and has a horizontal section installed to passthrough a lower sidewall of the reaction tube 203 and a vertical sectioninstalled to rise from one end side toward the other end side of atleast the wafer arrangement region. Gas supply holes 250 a configured tosupply a gas are installed at side surfaces of the first nozzle 249 a.The gas supply holes 250 a are opened toward a center of the reactiontube 203, and enable supply of the gas toward the wafers 200. Theplurality of gas supply holes 250 a are formed from a lower portion toan upper portion of the reaction tube 203, and have the same openingarea and are formed at the same opening pitch.

A first gas supply system is constituted by mainly the first gas supplypipe 232 a, the mass flow controller 241 a and the valve 243 a. Inaddition, the first nozzle 249 a may be included in the first gas supplysystem. Further, a first inert gas supply system is constituted bymainly the first inert gas supply pipe 232 e, the mass flow controller241 e and the valve 243 e. The first inert gas supply system functionsas a purge gas supply system.

A mass flow controller (MFC) 241 b, which is a flow rate controller (aflow rate control unit), and a valve 243 b, which is an opening/closingvalve, are installed at the second gas supply pipe 232 b in sequencefrom the upstream direction. In addition, a second inert gas supply pipe232 f is connected to the second gas supply pipe 232 b at a downstreamside of the valve 243 b. A mass flow controller 241 f, which is a flowrate controller (a flow rate control unit), and a valve 243 f, which isan opening/closing valve, are installed at the second inert gas supplypipe 232 f in sequence from the upstream direction. In addition, theabove-mentioned second nozzle 249 b is connected to a front end of thesecond gas supply pipe 232 b. The second nozzle 249 b is installed in anarc-shaped space between the inner wall of the reaction tube 203 and thewafers 200 from the lower portion to the upper portion of the inner wallof the reaction tube 203 to rise upward in the stacking direction of thewafers 200. That is, the second nozzle 249 b is installed in a sideregion of the wafer arrangement region, in which the wafers 200 arearranged, horizontally surrounding the wafer arrangement region alongthe wafer arrangement region. The second nozzle 249 b is constituted asan L-shaped long nozzle, and has a horizontal section installed to passthrough the lower sidewall of the reaction tube 203 and a verticalsection installed to rise from one end side toward the other end side ofat least the wafer arrangement region. Gas supply holes 250 b configuredto supply a gas are formed in side surfaces of the second nozzle 249 b.The gas supply holes 250 b are opened toward the center of the reactiontube 203, and enable supply of the gas toward the wafers 200. Theplurality of gas supply holes 250 b are formed from the lower portion tothe upper portion of the reaction tube 203, and have the same openingarea and are formed at the same opening pitch.

A second gas supply system is constituted by mainly the second gassupply pipe 232 b, the mass flow controller 241 b and the valve 243 b.In addition, the second nozzle 249 b may be included in the second gassupply system. Further, a second inert gas supply system is constitutedby mainly the second inert gas supply pipe 232 f, the mass flowcontroller 241 f and the valve 243 f. The second inert gas supply systemmay function as a purge gas supply system.

A mass flow controller (MFC) 241 c, which is a flow rate controller (aflow rate control unit), and a valve 243 c, which is an opening/closingvalve, are installed at the third gas supply pipe 232 c in sequence fromthe upstream direction. In addition, the fourth gas supply pipe 232 d isconnected to the third gas supply pipe 232 c at a downstream side of thevalve 243 c. A mass flow controller 241 d, which is a flow ratecontroller (a flow rate control unit), and a valve 243 d, which is anopening/closing valve, are installed at the fourth gas supply pipe 232 din sequence from the upstream direction. In addition, a third inert gassupply pipe 232 g is connected to the third gas supply pipe 232 c at adownstream side of the connecting position of the fourth gas supply pipe232 d. A mass flow controller 241 g, which is a flow rate controller (aflow rate control unit), and a valve 243 g, which is an opening/closingvalve, are installed at the third inert gas supply pipe 232 g insequence from the upstream direction. In addition, the above-mentionedthird nozzle 249 c is connected to a front end of the third gas supplypipe 232 c. The third nozzle 249 c is installed in an arc-shaped spacebetween the inner wall of the reaction tube 203 and the wafers 200 fromthe lower portion to the upper portion of the inner wall of the reactiontube 203 to rise upward in the stacking direction of the wafers 200.That is, the third nozzle 249 c is installed at a side region of thewafer arrangement region, in which the wafers 200 are arranged,horizontally surrounding the wafer arrangement region along the waferarrangement region. The third nozzle 249 c is configured as an L-shapedlong nozzle, and has a horizontal section installed to pass through thelower sidewall of the reaction tube 203 and a vertical section installedto rise from one end side toward the other end side of at least thewafer arrangement region. Gas supply holes 250 c configured to supply agas are installed in side surfaces of the third nozzle 249 c. The gassupply holes 250 c are opened toward the center of the reaction tube203, and enable supply of the gas toward the wafers 200. The pluralityof gas supply holes 250 c are installed from the lower portion to theupper portion of the reaction tube 203, and have the same opening areaand are formed at the same opening pitch.

A third gas supply system is constituted by mainly the third gas supplypipe 232 c, the mass flow controller 241 c and the valve 243 c. Inaddition, the third nozzle 249 c may be included in the third gas supplysystem. Further, a fourth gas supply system is constituted by mainly thefourth gas supply pipe 232 d, the mass flow controller 241 d and thevalve 243 d. Furthermore, the third nozzle 249 c may be included in thefourth gas supply system at a downstream side of the connecting positionof the third gas supply pipe 232 c with respect to the fourth gas supplypipe 232 d. In addition, a third inert gas supply system is constitutedby mainly the third inert gas supply pipe 232 g, the mass flowcontroller 241 g and the valve 243 g. The third inert gas supply systemalso functions as a purge gas supply system.

As described above, in the method of supplying a gas of the embodiment,the gas is conveyed via the nozzles 249 a, 249 b and 249 c disposed inan arc-shaped long space in a longitudinal direction defined by theinner wall of the reaction tube 203 and ends of the plurality of stackedwafers 200, the gas is first ejected into the reaction tube 203 near thewafers 200 through the gas supply holes 250 a, 250 b, 250 c opened inthe nozzles 249 a, 249 b and 249 c, respectively, and thus a main flowof the gas in the reaction tube 203 follows a direction parallel tosurfaces of the wafers 200, i.e., the horizontal direction. According tothe above-mentioned configuration, the gas can be uniformly supplied tothe wafers 200, and thus a film thickness of a thin film formed on eachof the wafers 200 can be uniformized. In addition, while the gas flowingon the surfaces of the wafers 200, i.e., a residual gas after reaction,flows toward an exhaust port, i.e., in a direction of the exhaust pipe231, a flow direction of the residual gas is not limited to the verticaldirection but may be appropriately specified by a position of theexhaust port.

A chlorosilane-based source gas, which is a source gas containing, forexample, at least silicon (Si) and chlorine (Cl), is supplied into theprocess chamber 201 via the mass flow controller 241 a, the valve 243 aand the first nozzle 249 a through the first gas supply pipe 232 a as asource gas containing a predetermined element and a halogen element.Here, the chlorosilane-based source gas refers to a chlorosilane-basedsource material in a gaseous state, for example, a gas obtained byvaporizing a chlorosilane-based source material in a liquid state undera normal temperature and a normal pressure, or a chlorosilane-basedsource material in a gaseous state under a normal temperature and anormal pressure. In addition, the chlorosilane-based source materialrefers to a silane-based source material containing a chloro group,which is a halogen group, and refers to a source material containing atleast silicon (Si) and chlorine (Cl). That is, the chlorosilane-basedsource material described herein may be referred to as a kind of halide.In addition, when the term “source material” is used herein, it mayrefer to “a liquid source material in a liquid state,” “a source gas ina gaseous state,” or both of these. Accordingly, when the term“chlorosilane-based source material” is used herein, it may refer to “achlorosilane-based source material in a liquid state,” “achlorosilane-based source gas in a gaseous state,” or both of these. Forexample, hexachlorodisilane (Si₂Cl₆, abbreviation: HCDS) gas containinghalogen ligands (Cl) may be used as the chlorosilane-based source gas.The number of the ligands (Cl) containing a halogen group of HCDS in onemolecule is 6. That is, the number of the ligands (Cl) containing ahalogen group of HCDS in the compositional formula of HCDS is 6. Inaddition, when the liquid source material in a liquid state under anormal temperature and a normal pressure like HCDS is used, the liquidsource material is vaporized by a vaporization system such as avaporizer or a bubbler to be supplied as a source gas (an HCDS gas).

A gas containing, for example, amine, i.e., an amine-based gas, issupplied into the process chamber 201 via the mass flow controller 241b, the valve 243 b and the second nozzle 249 b through the second gassupply pipe 232 b as a first reactive gas containing carbon (C) andnitrogen (N). Here, the amine-based gas refers to amine in a gaseousstate, for example, a gas containing amine group such as a gas obtainedby vaporizing amine in a liquid state under a normal temperature and anormal pressure, or amine in a gaseous state under a normal temperatureand a normal pressure. The amine-based gas contains amine such asethylamine, methylamine, propylamine, isopropylamine, butylamine,isobutylamine, or the like. Here, amine is a general name of compound inwhich a hydrogen element of ammonia (NH₃) is substituted with ahydrocarbon group such as an alkyl group. That is, amine contains ahydrocarbon group such as an alkyl group or the like as a ligandcontaining a carbon atom. The amine-based gas may be referred to as agas containing no silicon because the amine-based gas contains threeelements including carbon (C), nitrogen (N) and hydrogen (H) and doesnot contain silicon (Si), or may be referred to as a gas containing nosilicon and no metal because the amine-based gas does not containsilicon or metal. In addition, the amine-based gas may be anitrogen-containing gas, a carbon-containing gas, or ahydrogen-containing gas. The amine-based gas may be referred to as amaterial containing only the three elements including carbon (C),nitrogen (N) and hydrogen (H). In addition, when the term “amine” isused herein, it may refer to “amine in a liquid state,” “an amine-basedgas in a gaseous state,” or both of these. For example, triethylamine[(C₂H₅)₃N, abbreviation: TEA] gas containing ethyl ligands (C₂H₅) may beused as the amine-based gas. The number of the ligands (ethyl group)containing a carbon atom of TEA in one molecule is 3, that is, thenumber of the ligands (ethyl group) containing a carbon atom of TEA inthe compositional formula of TEA is 3. TEA has a composition wherein thenumber of carbon atoms is greater than that of nitrogen atoms. Inaddition, when amine in a liquid state under a normal temperature and anormal pressure such as TEA is used, the amine in a liquid state isvaporized by a vaporization system such as a vaporizer or a bubbler tobe supplied as a first reactive gas (TEA gas).

The first reactive gas has a composition wherein the number of carbonatoms is greater than that of nitrogen atoms. That is, the number ofcarbon atoms is greater than that of nitrogen atoms in the compositionalformula of the material constituting the first reactive gas. That is,the number of carbon atoms is greater than that of nitrogen atoms in onemolecule of the material constituting the first reaction gas.

Further, the first reaction gas contains a plurality of ligandscontaining carbon atoms. That is, a plurality of ligands containingcarbon atoms are contained in the compositional formula of the materialconstituting the first reactive gas.

For example, a gas containing oxygen (O) (an oxygen-containing gas),i.e., an oxidizing gas, is supplied into the process chamber 201 via themass flow controller 241 c, the valve 243 c and the third nozzle 249 cthrough the third gas supply pipe 232 c as a second reactive gasdifferent from the source gas and the first reactive gas. For example,oxygen (O₂) gas may be used as the oxygen-containing gas (the oxidizinggas).

For example, a gas containing nitrogen (N) (a nitrogen-containing gas),i.e., a nitriding gas, is supplied into the process chamber 201 via themass flow controller 241 d, the valve 243 d, the third gas supply pipe232 c and the third nozzle 249 c through the fourth gas supply pipe 232d as the second reactive gas different from the source gas and the firstreactive gas. For example, ammonia (NH₃) gas may be used as thenitrogen-containing gas (the nitriding gas).

For example, nitrogen (N₂) gas is supplied as an inert gas into theprocess chamber 201 via the mass flow controllers 241 e, 241 f and 241g, the valves 243 e, 243 f and 243 g, the gas supply pipes 232 a, 232 band 232 c, and the nozzles 249 a, 249 b and 249 c through inert gassupply pipes 232 e, 232 f and 232 g.

In addition, for example, when the above-mentioned gases flow throughthe gas supply pipes, a source gas supply system configured to supply asource gas containing a predetermined element and a halogen group, i.e.,a chlorosilane-based source gas supply system, is constituted by thefirst gas supply system. Further, the chlorosilane-based source gassupply system may be simply referred to as a chlorosilane-based sourcematerial supply system. Furthermore, a first reactive gas supply system,i.e., an amine-based gas supply system, is constituted by the second gassupply system. In addition, the amine-based gas supply system may besimply referred to as an amine supply system. Further, a second reactivegas supply system, i.e., an oxygen-containing gas supply system, whichis an oxidizing gas supply system, is constituted by the third gassupply system. Furthermore, a second reactive gas supply system, i.e., anitrogen-containing gas supply system, which is a nitriding gas supplysystem, is constituted by the fourth gas supply system.

The exhaust pipe 231 configured to exhaust an atmosphere in the processchamber 201 is installed at the reaction tube 203. As shown in FIG. 2,when seen in a horizontal cross-sectional view, the exhaust pipe 231 isinstalled at a side of the reaction tube 203 opposite to a side in whichthe gas supply hole 250 a of the first nozzle 249 a, the gas supply hole250 b of the second nozzle 249 b and the gas supply hole 250 c of thethird nozzle 249 c are formed, i.e., an opposite side of the gas supplyholes 250 a, 250 b and 250 c with the wafer 200 interposed therebetween.In addition, as shown in FIG. 1, when seen in a longitudinalcross-sectional view, the exhaust pipe 231 is installed under a place inwhich the gas supply holes 250 a, 250 b and 250 c are formed. Accordingto the above-mentioned configuration, the gas supplied near the wafers200 in the process chamber 201 through the gas supply holes 250 a, 250 band 250 c flows in the horizontal direction, i.e., a direction parallelto the surfaces of the wafers 200, and then flows downward to beexhausted through the exhaust pipe 231. As described above, a main flowof the gas in the process chamber 201 also becomes a flow in thehorizontal direction.

A vacuum pump 246, which is a vacuum exhaust apparatus, is connected tothe exhaust pipe 231 via a pressure sensor 245, which is a pressuredetector (a pressure detection unit), configured to detect a pressure inthe process chamber 201, and an auto pressure controller (APC) valve244, which is a pressure adjuster (a pressure adjusting unit). Inaddition, the APC valve 244 is a valve that can open/close a valve toperform vacuum exhaust and vacuum exhaust stoppage in the processchamber 201 in a state in which the vacuum pump 246 is operated, andthat can adjust a valve opening angle to adjust a pressure in theprocess chamber 201 in a state in which the vacuum pump 246 is operated.An exhaust system is constituted by mainly the exhaust pipe 231, the APCvalve 244 and the pressure sensor 245. In addition, the vacuum pump 246may be included in the exhaust system. The exhaust system is configuredto adjust the valve opening angle of the APC valve 244 based on pressureinformation detected by the pressure sensor 245 while operating thevacuum pump 246 such that the pressure in the process chamber 201 isvacuum-exhausted to a predetermined pressure (a vacuum level).

A seal cap 219, which is a furnace port cover configured to hermeticallyclose a lower end opening of the reaction tube 203, is installed underthe reaction tube 203. The seal cap 219 is configured to contact a lowerend of the reaction tube 203 from a lower side in the verticaldirection. The seal cap 219 is formed of metal such as stainless steel,and has a disc shape. An O-ring 220, which is a seal member in contactwith the lower end of the reaction tube 203, is installed at an uppersurface of the seal cap 219. A rotary mechanism 267 configured to rotatethe boat 217, which is a substrate holder (to be described later), isinstalled at the seal cap 219 opposite to the process chamber 201. Arotary shaft 255 of the rotary mechanism 267 passes through the seal cap219 to be connected to the boat 217. The rotary mechanism 267 isconfigured to rotate the wafers 200 by rotating the boat 217. The sealcap 219 is configured to be raised and lowered in the vertical directionby a boat elevator 115, which is an elevation mechanism verticallyinstalled at the outside of the reaction tube 203. The boat elevator 115is configured to load and unload the boat 217 into and from the processchamber 201 by raising and lowering the seal cap 219. That is, the boatelevator 115 is configured as a conveyance apparatus (a conveyancemechanism) configured to convey the boat 217, i.e., the wafers 200, intoand from the process chamber 201.

The boat 217, which is a substrate support, is formed of aheat-resistant material such as quartz or silicon carbide, andconfigured to concentrically align the plurality of wafers 200 in ahorizontal posture in a multi-stage manner. In addition, an adiabaticmember 218 formed of a heat-resistant material such as quartz or siliconcarbide is installed at a lower portion of the boat 217, and configuredsuch that heat from the heater 207 cannot be transferred to the seal cap219. In addition, the adiabatic member 218 may be constituted by aplurality of adiabatic plates formed of a heat-resistant material suchas quartz or silicon carbide, and an adiabatic plate holder configuredto support the adiabatic plates in a horizontal posture in a multi-stagemanner.

A temperature sensor 263, which is a temperature detector, is installedin the reaction tube 203, and configured to adjust an electricalconnection state to the heater 207 based on temperature informationdetected by the temperature sensor 263 such that the temperature in theprocess chamber 201 reaches a desired temperature distribution. Thetemperature sensor 263 is constituted in an L shape like the nozzles 249a, 249 b and 249 c, and installed along the inner wall of the reactiontube 203.

As shown in FIG. 3, a controller 121, which is a control unit (a controlpart), is configured as a computer including a central processing unit(CPU) 121 a, a random access memory (RAM) 121 b, a memory device 121 c,and an I/O port 121 d. The RAM 121 b, the memory device 121 c and theI/O port 121 d are configured to exchange data with the CPU 121 a via aninternal bus 121 e. An input/output device 122 formed of, for example, atouch panel, is connected to the controller 121.

The memory device 121 c is constituted by, for example, a flash memory,a hard disk drive (HDD), or the like. A control program for controllingan operation of the substrate processing apparatus or a process recipe,in which a sequence or condition for processing a substrate (to bedescribed later) is written, is readably stored in the memory device 121c. In addition, the process recipe, which functions as a program, iscombined to execute each sequence in the substrate processing process(to be described later) in the controller 121 to obtain a predeterminedresult. Hereinafter, the process recipe or control program may begenerally simply referred to as a program. In addition, when term“program” is used herein, it may include the case in which the processrecipe is solely included, the case in which the control program issolely included, or the case in which both of these are included. Inaddition, the RAM 121 b is configured as a memory region (a work area)in which a program or data read by the CPU 121 a is temporarily stored.

The I/O port 121 d is connected to the mass flow controllers 241 a, 241b, 241 c, 241 d, 241 e, 241 f and 241 g, the valves 243 a, 243 b, 243 c,243 d, 243 e, 243 f and 243 g, the pressure sensor 245, the APC valve244, the vacuum pump 246, the heater 207, the temperature sensor 263,the rotary mechanism 267, the boat elevator 115, and so on.

The CPU 121 a is configured to read and execute the control program fromthe memory device 121 c and read the process recipe from the memorydevice 121 c according to input of an operation command from theinput/output device 122. In addition, the CPU 121 a is configured tocontrol flow rate controlling operations of various gases by the massflow controllers 241 a, 241 b, 241 c, 241 d, 241 e, 241 f and 241 gaccording to contents of the read process recipe, opening/closingoperations of the valves 243 a, 243 b, 243 c, 243 d, 243 e, 243 f and243 g, an opening/closing operation of the APC valve 244 and a pressureadjusting operation by the APC valve 244 based on the pressure sensor245, a temperature adjusting operation of the heater 207 based on thetemperature sensor 263, start and stop of the vacuum pump 246, arotation and rotation speed adjustment operation of the boat 217 by therotary mechanism 267, an elevation operation of the boat 217 by the boatelevator 115, and so on.

In addition, the controller 121 is not limited to being configured as anexclusive computer but may be configured as a general-purpose computer.For example, the controller 121 according to the embodiment can beconfigured by preparing an external memory device 123, in which theprogram is stored [for example, a magnetic tape, a magnetic disk such asa flexible disk or a hard disk, an optical disc such as a CD or DVD, anoptomagnetic disc such as an MO, a semiconductor memory such as a USBmemory or a memory card], and installing the program on thegeneral-purpose computer using the external memory device 123. Inaddition, a unit configured to supply a program to a computer is notlimited to the case in which the program is supplied via the externalmemory device 123. For example, the program may be supplied using acommunication means such as the Internet or a dedicated line, ratherthan via the external memory device 123. Further, the memory device 121c or the external memory device 123 is configured as a non-transitorycomputer readable recording medium, which is readable by a computer.Hereinafter, these are generally simply referred to as recording media.Furthermore, when the term “non-transitory computer readable recordingmedium” is used herein, it may include the case in which the memorydevice 121 c is solely included, the case in which the external memorydevice 123 is solely included, or the case in which both of these areincluded.

(2) Substrate Processing Process

Next, an example of forming a thin film on the wafer 200, which is oneprocess of a process of manufacturing a semiconductor device using theprocessing furnace 202 of the above-mentioned substrate processingapparatus, will be described. In addition, in the following description,operations of the respective parts constituting the substrate processingapparatus are controlled by the controller 121.

In the embodiment, a cycle including a process in which a process ofsupplying a source gas containing a predetermined element and a halogenelement to the wafer 200 in the process chamber 201 and a process ofsupplying a first reactive gas containing the three elements includingcarbon, nitrogen and hydrogen and having a composition wherein thenumber of carbon atoms is greater than that of nitrogen atoms in onemolecule to the wafer 200 in the process chamber 201 are alternatelyperformed a predetermined number of times (one or more) to form a firstlayer containing the predetermined element, nitrogen and carbon on thewafer 200; and a process of supplying a second reactive gas differentfrom the source gas and the first reactive gas to the wafer 200 in theprocess chamber 201 and modifying the first layer to form a secondlayer, is performed a predetermined number of times (one or more) toform a thin film having a predetermined composition containing thepredetermined element and a predetermined film thickness on the wafer200.

In addition, in the embodiment, in order to form a composition ratio ofa thin film to be formed as a stoichiometric composition or anotherpredetermined composition ratio different from the stoichiometriccomposition, supply conditions of a plurality of kinds of gasescontaining a plurality of elements constituting the thin film to beformed are controlled. For example, the supply conditions are controlledsuch that at least one element of the plurality of elements constitutingthe thin film to be formed stoichiometrically exceeds another element.Hereinafter, an example of forming a film while controlling a ratio ofthe plurality of elements constituting the thin film to be formed, i.e.,a composition ratio of the thin film, will be described.

Hereinafter, the film-forming sequence of the embodiment will bedescribed in detail with reference to FIGS. 4 and 5. FIG. 4 is a viewshowing a film-forming flow of the embodiment. FIG. 5 is a view showinga gas supply timing in the film-forming sequence of the embodiment.

In addition, here, an example in which a cycle including a process inwhich a process of supplying an HCDS gas, which is a chlorosilane-basedsource gas, to the wafer 200 in the process chamber 201 as a source gasand a process of supplying TEA gas, which is an amine-based gascontaining a plurality of (three) ligands (ethyl groups) containing acarbon atom in one molecule, to the wafer 200 in the process chamber 201as a first reactive gas containing the three elements including carbon,nitrogen and hydrogen and having a composition wherein the number ofcarbon atoms is greater than that of nitrogen atoms in one molecule arealternately performed once to form a first layer containing silicon,nitrogen and carbon on the wafer 200; and a process of supplying O₂ gas,which is an oxygen-containing gas (an oxidizing gas), as a secondreactive gas different from the source gas and the first reactive gas tothe wafer 200 in the process chamber 201 and modifying the first layerto form a silicon oxycarbonitride layer (a SiOCN layer) or a siliconoxycarbide layer (a SiOC layer) as a second layer, is performed apredetermined number of times (n times) to form a siliconoxycarbonitride film (a SiOCN film) or a silicon oxycarbide film (a SiOCfilm), which is a silicon-based insulating film having a predeterminedcomposition and a predetermined film thickness, on the wafer 200 will bedescribed.

In addition, when the term “wafer” is used herein, it may refer to “thewafer itself” or “the wafer and a stacked body (a collected body) ofpredetermined layers or films formed on the surface” (i.e., the waferincluding the predetermined layers or films formed on the surface may bereferred to as a wafer). In addition, the phrase “a surface of a wafer”as used herein may refer to “a surface (an exposed surface) of a waferitself” or “a surface of a predetermined layer or film formed on thewafer, i.e., the uppermost surface of the wafer, which is a stackedbody.”

Accordingly, when “a predetermined gas is supplied to a wafer” iswritten herein, it may mean that “a predetermined gas is directlysupplied to a surface (exposed surface) of a wafer itself” or that “apredetermined gas is supplied to a layer or a film formed on a wafer,i.e., on the uppermost surface of a wafer as a stacked body.” Inaddition, when “a predetermined layer (of film) is formed on a wafer” iswritten herein, it may mean that “a predetermined layer (or film) isdirectly formed on a surface (an exposed surface) of a wafer itself” orthat “a predetermined layer (or film) is formed on a layer or a filmformed on a wafer, i.e., on the uppermost surface of a wafer as astacked body.”

In addition, the term “substrate” as used herein may be synonymous withthe term “wafer,” and in this case, the terms “wafer” and “substrate”may be used interchangeably.

Wafer Charging and Boat Loading

When the plurality of wafers 200 are charged on the boat 217 (wafercharging), as shown in FIG. 1, the boat 217 supporting the plurality ofwafers 200 is raised by the boat elevator 115 to be loaded into theprocess chamber 201 (boat loading). In this state, the seal cap 219hermetically seals the lower end of the reaction tube 203 via the O-ring220.

Pressure Adjustment and Temperature Adjustment

The inside of the process chamber 201 is vacuum-exhausted by the vacuumpump 246 to a desired pressure (a vacuum level). Here, the pressure inthe process chamber 201 is measured by the pressure sensor 245, and theAPC valve 244 is feedback-controlled based on the measured pressureinformation (pressure adjustment). In addition, the vacuum pump 246maintains a regular operation state at least until processing of thewafers 200 is terminated. Further, the process chamber 201 is heated bythe heater 207 to a desired temperature. Here, an electrical connectionstate to the heater 207 is feedback-controlled based on the temperatureinformation detected by the temperature sensor 263 until the inside ofthe process chamber 201 reaches a desired temperature distribution(temperature adjustment). In addition, heating of the inside of theprocess chamber 201 by the heater 207 is continuously performed at leastuntil processing of the wafers 200 is terminated. Next, rotation of theboat 217 and the wafers 200 is started by the rotary mechanism 267. Inaddition, rotation of the boat 217 and the wafers 200 by the rotarymechanism 267 is continuously performed at least until processing of thewafers 200 is terminated.

Process of Forming Silicon Oxycarbonitride Film or Silicon OxycarbideFilm

Next, the following three steps, i.e., steps 1 to 3, are sequentiallyperformed.

[Step 1]

HCDS Gas Supply

The valve 243 a of the first gas supply pipe 232 a is opened to flowHCDS gas in the first gas supply pipe 232 a. A flow rate of the HCDS gasflowing in the first gas supply pipe 232 a is controlled by the massflow controller 241 a. The flow rate-controlled HCDS gas is suppliedinto the process chamber 201 through the gas supply hole 250 a of thefirst nozzle 249 a to be exhausted through the exhaust pipe 231. Here,the HCDS gas is supplied to the wafer 200. At the same time, the valve243 e is opened to flow N₂ gas, which is an inert gas, into the firstinert gas supply pipe 232 e. A flow rate of the N₂ gas flowing in thefirst inert gas supply pipe 232 e is controlled by the mass flowcontroller 241 e. The flow rate-controlled N₂ gas is supplied into theprocess chamber 201 with the HCDS gas to be exhausted through theexhaust pipe 231.

In addition, here, in order to prevent infiltration of the HCDS gas intothe second nozzle 249 b and the third nozzle 249 c, the valves 243 f and243 g are opened to flow the N₂ gas into the second inert gas supplypipe 232 f and the third inert gas supply pipe 232 g. The N₂ gas issupplied into the process chamber 201 via the second gas supply pipe 232b, the third gas supply pipe 232 c, the second nozzle 249 b and thethird nozzle 249 c to be exhausted through the exhaust pipe 231.

Here, the APC valve 244 is appropriately adjusted to vary the pressurein the process chamber 201 to a pressure within a range of, for example,1 to 13,300 Pa, preferably, 20 to 1,330 Pa. A supply flow rate of theHCDS gas controlled by the mass flow controller 241 a is set to a flowrate within a range of, for example, 1 to 1,000 sccm. Supply flow ratesof the N₂ gas controlled by the mass flow controllers 241 e, 241 f and241 g are set to flow rates within a range of, for example, 100 to10,000 sccm. A time of supplying the HCDS gas to the wafer 200, i.e., agas supply time (an irradiation time), is a time within a range of, forexample, 1 to 120 seconds, preferably, 1 to 60 seconds. Here, atemperature of the heater 207 is set such that a temperature of thewafer 200 is a temperature within a range of, for example, 250 to 700°C., preferably 300 to 650° C., and more preferably, 350 to 600° C. Inaddition, when the temperature of the wafer 200 is less than 250° C.,the HCDS cannot be easily chemisorbed onto the wafer 200 such that apractical film-forming rate cannot be obtained. This problem can besolved by increasing the temperature of the wafer 200 to 250° C. ormore. In addition, the HCDS can be more sufficiently adsorbed onto thewafer 200 by increasing the temperature of the wafer 200 to 300° C. ormore, or 350° C. or more, and a more sufficient film-forming rate can beobtained. Further, when the temperature of the wafer 200 exceeds 700°C., film thickness uniformity may be easily deteriorated to make itdifficult to control the film thickness uniformity as a CVD reaction isstrengthened (a gaseous reaction becomes dominant). Deterioration of thefilm thickness uniformity can be suppressed and control thereof can beperformed by controlling the temperature of the wafer 200 to 700° C. orless. In particular, a surface reaction becomes dominant by controllingthe temperature of the wafer 200 to 650° C. or less, or 600° C. or less,the film thickness uniformity can be easily secured, and control thereofbecomes easy. Accordingly, the temperature of the wafer 200 may be atemperature within a range of 250 to 700° C., preferably 300 to 650° C.,more preferably 350 to 600° C.

The HCDS gas is supplied to the wafer 200 under the above-mentionedconditions, and for example, a silicon-containing layer containingchlorine (Cl) having a thickness of about less than one atomic layer toseveral atomic layers is formed on the wafer 200 (a lower base film of asurface) as an initial layer containing a predetermined element(silicon) and a halogen element (chlorine). The silicon-containing layercontaining Cl may be an adsorption layer of the HCDS gas, a siliconlayer (a Si layer) containing Cl, or both of these.

Here, the silicon layer containing Cl is a generic name including adiscontinuous layer in addition to a continuous layer formed of silicon(Si) and containing Cl, or a silicon thin film containing Cl formed byoverlapping them. In addition, a continuous layer formed of Si andcontaining Cl may be referred to as the silicon thin film containing Cl.Further, Si constituting the silicon layer containing Cl contains Si, inwhich bonding to Cl is completely broken, in addition to Si, in whichbonding to Cl is not completely broken.

In addition, the adsorption layer of the HCDS gas includes achemisorption layer in which a gas molecules of the HCDS gas arediscontinuous, in addition to the chemisorption layer in which the gasmolecules of the HCDS gas are continuous. That is, the adsorption layerof the HCDS gas includes a chemisorption layer having a thickness of onemolecular layer containing HCDS molecules or less than one molecularlayer. Further, HCDS (Si₂Cl₆) molecules constituting the adsorptionlayer of the HCDS gas contains molecules in which bonding of Si and Clis partially broken (a Si_(x)Cl_(y) molecule). That is, the adsorptionlayer of the HCDS includes a chemisorption layer in which Si₂Cl₆molecules and/or Si_(x)Cl_(y) molecules are continuous, or achemisorption layer in which Si₂Cl₆ molecules and/or Si_(x)Cl_(y)molecules are discontinuous.

In addition, a layer having a thickness of less than one atomic layerrefers to a discontinuously formed atomic layer, and a layer having athickness of one atomic layer refers to a continuously formed atomiclayer. Further, a layer having a thickness of less than one molecularlayer refers to a discontinuously formed molecular layer, and a layerhaving a thickness of one molecular layer refers to a continuouslyformed molecular layer.

Under conditions in which the HCDS gas is autolyzed (pyrolyzed), i.e.,under conditions in which a pyrolysis reaction of the HCDS occurs, thesilicon layer containing Cl is formed by depositing Si on the wafer 200.Under conditions in which the HCDS gas is not autolyzed (pyrolyzed),i.e., under conditions in which a pyrolysis reaction of the HCDS doesnot occur, the adsorption layer of the HCDS gas is formed by adsorbingthe HCDS gas onto the wafer 200. In addition, formation of theadsorption layer of the HCDS gas on the wafer 200 can increase thefilm-forming rate more than formation of the silicon layer containing Clon the wafer 200.

When the thickness of the silicon-containing layer containing Cl formedon the wafer 200 exceeds several atomic layers, an effect ofmodification in step 2 and step 3 (described later) is not transferredto the entire silicon-containing layer containing Cl. In addition, aminimum value of the thickness of the silicon-containing layercontaining Cl that can be formed on the wafer 200 is less than oneatomic layer. Accordingly, the thickness of the silicon-containing layercontaining Cl may be less than one atomic layer to several atomiclayers. In addition, as the thickness of the silicon-containing layercontaining Cl is one atomic layer or less, i.e., one atomic layer orless than one atomic layer, an effect of the modification reaction instep 2 and step 3 (to be described later) can be relatively increased,and a time required for the modification reaction in step 2 and step 3can be reduced. A time for forming the silicon-containing layercontaining Cl in step 1 can be reduced. Eventually, a processing timeper one cycle can be reduced, and a total processing time can also bereduced. That is, the film-forming rate can also be increased. Inaddition, as the thickness of the silicon-containing layer containing Clis one atomic layer or less, controllability of the film thicknessuniformity can also be increased.

Removal of Residual Gas

After the silicon-containing layer containing Cl is formed as an initiallayer, the valve 243 a of the first gas supply pipe 232 a is closed tostop supply of the HCDS gas. Here, the APC valve 244 of the exhaust pipe231 is in an open state, and the inside of the process chamber 201 isvacuum-exhausted by the vacuum pump 246 to remove the HCDS gas remainingin the process chamber 201 after non-reaction or contribution toformation of the initial layer from the process chamber 201. Inaddition, here, supply of the N₂ gas, which is an inert gas, into theprocess chamber 201 is maintained in a state in which the valves 243 e,243 f and 243 g are open. The N₂ gas acts as a purge gas, and thus, theHCDS gas remaining in the process chamber 201 after non-reaction orcontribution to formation of the initial layer can be removed from theinside of the process chamber 201.

In addition, here, the gas remaining in the process chamber 201 may notbe completely removed, and the inside of the process chamber 201 may notbe completely purged. When the gas remaining in the process chamber 201is very small in amount, there is no bad effect generated in step 2performed thereafter. Here, a flow rate of the N₂ gas supplied into theprocess chamber 201 need not be a large flow rate, and for example, anamount of N₂ gas similar to a capacity of the reaction tube 203 (theprocess chamber 201) can be supplied to perform the purge such thatthere is no bad effect generated in step 2. As described above, as theinside of the process chamber 201 is not completely purged, the purgetime can be reduced to improve throughput. In addition, consumption ofN₂ gas can be suppressed to a minimal necessity.

An inorganic source gas such as a tetrachlorosilane e.g., silicontetrachloride (SiCl₄, abbreviation: STC) gas, trichlorosilane (SiHCl₃,abbreviation: TCS) gas, dichlorosilane (SiH₂Cl₂, abbreviation: DCS) gas,monochlorosilane (SiH₃Cl, abbreviation: MCS) gas, or the like, inaddition to hexachlorodisilane (Si₂Cl₆, abbreviation: HCDS) gas, may beused as the chlorosilane-based source gas. A rare gas such as Ar gas, Hegas, Ne gas, Xe gas, or the like, in addition to N₂ gas, may be used asthe inert gas.

[Step 2]

TEA Gas Supply

After step 1 is terminated and the residual gas in the process chamber201 is removed, the valve 243 b of the second gas supply pipe 232 b isopened to flow TEA gas into the second gas supply pipe 232 b. A flowrate of TEA gas flowing in the second gas supply pipe 232 b is adjustedby the mass flow controller 241 b. The flow rate-adjusted TEA gas issupplied into the process chamber 201 through the gas supply hole 250 bof the second nozzle 249 b. The TEA gas supplied into the processchamber 201 is thermally activated (excited) and exhausted through theexhaust pipe 231. Here, the thermally activated TEA gas is supplied tothe wafer 200. At the same time, the valve 243 f is opened to flow theN₂ gas, which is an inert gas, into the second inert gas supply pipe 232f. A flow rate of the N₂ gas flowing in the second inert gas supply pipe232 f is adjusted by the mass flow controller 241 f. The flowrate-adjusted N₂ gas is supplied into the process chamber 201 with theTEA gas to be exhausted through the exhaust pipe 231.

In addition, here, in order to prevent infiltration of the TEA gas intothe first nozzle 249 a and the third nozzle 249 c, the valves 243 e and243 g are opened to flow the N₂ gas into the first inert gas supply pipe232 e and the third inert gas supply pipe 232 g. The N₂ gas is suppliedinto the process chamber 201 via the first gas supply pipe 232 a, thethird gas supply pipe 232 c, the first nozzle 249 a and the third nozzle249 c to be exhausted through the exhaust pipe 231.

Here, the APC valve 244 is appropriately adjusted such that the pressurein the process chamber 201 becomes a pressure within a range of, forexample, 1 to 13,300 Pa, preferably 399 to 3,990 Pa. As the pressure inthe process chamber 201 is set to be a relatively high pressure range,the TEA gas can be thermally activated with non-plasma. In addition,since the TEA gas can be thermally activated and supplied to generate asoft reaction, the modification (to be described later) can be softlyperformed. A supply flow rate of the TEA gas controlled by the mass flowcontroller 241 b is set to a flow rate within a range of, for example,100 to 2,000 sccm. Supply flow rates of the N₂ gas controlled by themass flow controllers 241 f, 241 e and 241 g are set to flow rateswithin a range of, for example, 100 to 10,000 sccm. Here, a partialpressure of the TEA gas in the process chamber 201 is set to a pressurewithin a range of 0.01 to 12,667 Pa. A time for supplying the thermallyactivated TEA gas to the wafer 200, i.e., the gas supply time (theirradiation time), is set to a time within a range of, for example, 1 to120 seconds, preferably, 1 to 60 seconds. Here, similar to step 1, thetemperature of the heater 207 is set such that the temperature of thewafer 200 is a temperature within a range of, for example, 250 to 700°C., preferably 300 to 650° C., and more preferably 350 to 600° C.

As the TEA gas is supplied to the wafer 200 under the above-mentionedconditions, the silicon-containing layer containing Cl, which is theinitial layer, formed on the wafer 200 in step 1 can be reacted with theTEA gas. That is, a halogen element (Cl) contained in thesilicon-containing layer containing Cl as the initial layer can bereacted with a ligand (an ethyl group) contained in the TEA gas.Accordingly, at least some of Cl atoms, i.e., atoms of halogen elementcontained in the initial layer can be drawn (separated) from the initiallayer, and at least some of a plurality of ethyl groups contained in theTEA gas can be separated from the TEA gas. In addition, N of the TEA gasfrom which at least some of the ethyl groups are separated can be bondedto Si contained in the initial layer. That is, N constituting the TEAgas and having a dangling bond due to removal of at least some of theethyl groups can be bonded to Si contained in the initial layer andhaving a dangling bond or Si in which a dangling bond had been providedto form Si—N bonding. In addition, here, C contained in the ethyl group,which is a ligand of TEA gas, or C that had been contained in the ethylgroup can also be bonded to Si contained in the initial layer to formSi—C bonding. As a result, Cl is separated from the initial layer and anN element is newly introduced into the initial layer. In addition, here,a C element is also newly introduced into the initial layer.

As the TEA gas is supplied under the above-mentioned conditions, thesilicon-containing layer containing Cl, which is the initial layer, canbe appropriately reacted with the TEA gas, and the above-mentionedseries of reactions can be generated.

Cl is separated from the initial layer by the series of reactions, an Nelement and a C element are newly introduced into the initial layer, andthe silicon-containing layer containing Cl, which is the initial layer,is changed (modified) into a first layer containing silicon (Si),nitrogen (N) and carbon (C), i.e., a silicon carbonitride layer (a SiCNlayer). The first layer becomes a layer having a thickness of less thanone atomic layer to several atomic layers and containing Si, N and C. Inaddition, the first layer is a layer in which a ratio of a Si element ora ratio of C element is relatively high, i.e., a Si-rich or C-richlayer.

In addition, when a layer containing Si, N and C is formed as the firstlayer, chlorine (Cl) that had been contained in the silicon-containinglayer containing Cl or hydrogen (H) that had been contained in the TEAgas constitute a gaseous material, for example, chlorine (Cl₂) gas,hydrogen (H₂) gas or hydrogen chloride (HCl) gas during a process ofmodification reaction of the silicon-containing layer containing Cl bythe TEA gas to be discharged from the process chamber 201 via theexhaust pipe 231. That is, impurities such as Cl in the initial layerare drawn or eliminated from the initial layer to be separated from theinitial layer. Accordingly, the first layer becomes a layer having fewerimpurities such as Cl than the initial layer.

Removal of Residual Gas

After the first layer is formed, the valve 243 b of the second gassupply pipe 232 b is closed to stop supply of the TEA gas. Here, theinside of the process chamber 201 is vacuum-exhausted by the vacuum pump246 in a state in which the APC valve 244 of the exhaust pipe 231 isopen, and the TEA gas or reaction byproduct remaining in the processchamber 201 after non-reaction or contribution to formation of the firstlayer is removed from the inside of the process chamber 201. Inaddition, here, supply of the N₂ gas, which is an inert gas, into theprocess chamber 201 is maintained in a state in which the valves 243 f,243 e and 243 g are open. The N₂ gas acts as a purge gas, and thus theTEA gas or reaction byproduct remaining in the process chamber 201 afternon-reaction or contribution to formation of the first layer can beeffectively removed from the process chamber 201.

In addition, here, the gas remaining in the process chamber 201 may notbe completely removed, or the inside of the process chamber 201 may notbe completely purged. When the amount of gas remaining in the processchamber 201 is very small, there is no bad affect generated in step 3performed thereafter. Here, the flow rate of the N₂ gas supplied intothe process chamber 201 need not be set to a large flow rate, and forexample, the amount of the N₂ gas similar to a capacity of the reactiontube 203 (the process chamber 201) can be supplied to perform the purgesuch that there is no bad affect generated in step 3. As describedabove, as the inside of the process chamber 201 is not completelypurged, the purge time can be reduced to improve throughput. Inaddition, consumption of the N₂ gas can be suppressed to a minimalnecessity.

As the amine-based gas, in addition to triethylamine [(C₂H₅)₃N,abbreviation: TEA], an ethylamine-based gas obtained by vaporizingdiethylamine [(C₂H₅)₂NH, abbreviation: DEA] or monoethylamine (C₂H₅NH₂,abbreviation: MEA), a methylamine-based gas obtained by vaporizingtrimethylamine [(CH₃)₃N, abbreviation: TMA], dimethyl amine [(CH₃)₂NH,abbreviation: DMA] or monomethylamine (CH₃NH₂, abbreviation: MMA), apropylamine-based gas obtained by vaporizing tripropylamine [(C₃H₇)₃N,abbreviation: TPA], dipropylamine [(C₃H₇)₂NH, abbreviation: DPA] ormonopropylamine (C₃H₇NH₂, abbreviation: MPA), an isopropylamine-basedgas obtained by vaporizing, triisopropylamine ([(CH₃)₂CH]₃N,abbreviation: TIPA), diisopropylamine ([(CH₃)₂CH]₂NH, abbreviation:DIPA) or monoisopropylamine [(CH₃)₂CHNH₂, abbreviation: MIPA], abutylamine-based gas obtained by vaporizing tributylamine [(C₄H₉)₃N,abbreviation: TBA], dibutyl amine [(C₄H₉)₂NH, abbreviation: DBA] ormonobutylamine (C₄H₉NH₂, abbreviation: MBA), or an isobutylamine-basedgas obtained by vaporizing triisobutylamine ([(CH₃)₂CHCH₂]₃N,abbreviation: TIBA), diisobutylamine ([(CH₃)₂CHCH₂]₂NH, abbreviation:DIBA) or monoisobutylamine [(CH₃)₂CHCH₂NH₂, abbreviation: MIBA] may beused. That is, for example, at least one gas of (C₂H₅)_(x)N_(3-x),(CH₃)_(x)NH_(3-x), (C₃H₇)_(x)NH_(3-x), [(CH₃)₂CH]_(x)NH_(3-x),(C₄H₉)_(x)NH_(3-x), and [(CH₃)₂CHCH₂]_(x)NH_(3-x) (in equations, x is aninteger of 1 to 3) may be used as the amine-based gas.

In addition, a gas containing the three elements including carbon,nitrogen and hydrogen and having a composition wherein the number ofcarbon atoms is greater than that of nitrogen atoms in one molecule maybe used as the amine-based gas. That is, a gas containing at least oneamine selected from the group consisting of TEA, DEA, MEA, TMA, DMA,TPA, DPA, MPA, TIPA, DIPA, MIPA, TBA, DBA, MBA, TIBA, DIBA and MIBA maybe used as the amine-based gas.

When a chlorosilane-based source gas containing a predetermined element(silicon) and a halogen element (chlorine) such as HCDS gas is used as asource gas, as the amine-based gas containing the three elementsincluding carbon, nitrogen and hydrogen and having a composition whereinthe number of carbon atoms is greater than that of nitrogen atom in onemolecule such as TEA gas or DEA gas is used as the first reactive gas, acarbon concentration in the first layer formed in step 2, i.e., a carbonconcentration in a SiOCN film or a SiOC film formed by processesperformed a predetermined number of times (to be described later) can beincreased.

On the other hand, when the chlorosilane-based source gas containing apredetermined element (silicon) and a halogen element (chlorine) such asHCDS gas is used as a source gas, the case in which a gas containing thethree elements including carbon, nitrogen and hydrogen and having acomposition wherein the number of carbon atoms is not greater than thatof nitrogen atoms in one molecule such as an amine-based gas, forexample, MMA gas, or an organic hydrazine-based gas, for example, MMHgas or DMH gas (to be described later) is used as the first reactivegas, the carbon concentration of the first layer, i.e., the carbonconcentration in the SiOCN film or the SiOC film cannot be increased toa level similar to the case in which the amine-based gas containing thethree elements including carbon, nitrogen and hydrogen and having acomposition wherein the number of carbon atoms is greater than that ofnitrogen atoms in one molecule is used as the first reactive gas, andthus, an appropriate carbon concentration cannot be easily realized.

In addition, a gas containing a plurality of ligands containing a carbon(C) atom in one molecule, i.e., a gas containing a plurality ofhydrocarbon groups such as alkyl groups in one molecule may be used asthe amine-based gas. Specifically, a gas having three or two ligands (ahydrocarbon group such as an alkyl group) containing a carbon (C) atomin one molecule may be used as the amine-based gas, and for example, agas containing at least one amine selected from the group consisting ofTEA, DEA, TMA, DMA, TPA, DPA, TWA, DIPA, TBA, DBA, TIBA and MBA may beused.

When the chlorosilane-based source gas containing a predeterminedelement (silicon) and a halogen element (chlorine) such as HCDS gas isused as a source gas, as the amine-based gas containing the threeelements including carbon, nitrogen and hydrogen and containing aplurality of ligands containing a carbon atom in one molecule such asTEA gas or DEA gas, i.e., the amine-based gas containing a plurality ofhydrocarbon groups such as alkyl groups in one molecule is used as thefirst reactive gas, the carbon concentration in the first layer, i.e.,the carbon concentration in the SiOCN film or the SiOC film can befurther improved.

On the other hand, when the chlorosilane-based source gas containingsilicon and a halogen element (chlorine) such as HCDS gas is used as asource gas, as the case in which a gas that does not include a pluralityof ligands containing a carbon atom in one molecule such as anamine-based gas, for example, MMA gas, or an organic hydrazine-based gasto be described later, for example, MMH gas, is used as the firstreactive gas, the carbon concentration in the first layer, i.e., thecarbon concentration in the SiOCN film or the SiOC film, cannot beincreased to a level similar to the case in which the amine-based gascontaining a plurality of ligands containing a carbon atom in onemolecule is used as the first reactive gas, and an appropriate carbonconcentration cannot be easily realized.

As the amine-based gas containing two ligands (hydrocarbon groups suchas alkyl groups) containing a carbon atom in one molecule such as DEAgas is used as the first reactive gas, in comparison with the case inwhich the amine-based gas containing three ligands (hydrocarbon groupssuch as alkyl groups) containing a carbon atom in one molecule such asTEA gas is used, a cycle rate (a thickness of the SiOCN layer or theSiOC layer formed at each unit cycle) can be improved, and a ratio of anitrogen concentration with respect to a carbon concentration in thefirst layer (a ratio of the nitrogen concentration/the carbonconcentration), i.e., a ratio of the nitrogen concentration with respectto the carbon concentration (a ratio of the nitrogen concentration/thecarbon concentration) in the SiOCN film or the SiOC film can beincreased.

On the other hand, as the amine-based gas containing three ligands(hydrocarbon groups such as alkyl groups) containing a carbon atom inone molecule such as TEA gas is used as the first reactive gas, incomparison with the case in which the amine-based gas containing twoligands (hydrocarbon groups such as alkyl groups) containing a carbonatom in one molecule such as DEA gas is used, a ratio of the carbonconcentration with respect to the nitrogen concentration (a ratio of thecarbon concentration/the nitrogen concentration) in the first layer,i.e., a ratio of the carbon concentration with respect to the nitrogenconcentration (a ratio of the carbon concentration/the nitrogenconcentration) in the SiOCN film or the SiOC film, can be increased.

That is, the cycle rate or the nitrogen concentration or carbonconcentration in the formed SiOCN film or SiOC film can be finelyadjusted by the number of ligands (the number of hydrocarbon groups suchas alkyl groups) containing a carbon atom contained in the firstreactive gas, i.e., by varying a gas species of the first reactive gas.

In addition, while the fact that the carbon concentration in the SiOCNfilm or the SiOC film can be increased by appropriately selecting thegas species (composition) of the amine-based gas, which is the firstreactive gas, is similar to the above description, in order to furtherincrease the carbon concentration, for example, the pressure in theprocess chamber 201 when the amine-based gas (TEA gas) is supplied tothe wafer 200 may be higher than the pressure in the process chamber 201when the chlorosilane-based source gas (HCDS gas) is supplied to thewafer 200 in step 1, and further, higher than the pressure in theprocess chamber 201 when an oxygen-containing gas (O₂ gas) is suppliedto the wafer 200 in step 3 (to be described later). Further, in thiscase, the pressure in the process chamber 201 when the O₂ gas issupplied to the wafer 200 in step 3 may be higher than the pressure inthe process chamber 201 when the HCDS gas is supplied to the wafer 200in step 1. That is, provided that the pressure in the process chamber201 when the HCDS gas is supplied to the wafer 200 is P₁ [Pa], thepressure in the process chamber 201 when the TEA gas is supplied to thewafer 200 is P₂ [Pa], and the pressure in the process chamber 201 whenthe O₂ gas is supplied to the wafer 200 is P₃ [Pa], the pressures P₁ toP₃ may be set to satisfy, preferably, a relation of P₂>P₁, P₃, and morepreferably, a relation of P₂>P₃>P₁. That is, the pressure in the processchamber 201 when the TEA gas is supplied to the wafer 200 may be highestin steps 1 to 3.

On the other hand, in order to appropriately suppress an increment ofthe carbon concentration of the SiOCN film or the SiOC film, thepressure in the process chamber 201 when the amine-based gas (TEA gas)is supplied to the wafer 200 may be set to a pressure equal to or lessthan the pressure in the process chamber 201 when the oxygen-containinggas (O₂ gas) is supplied to the wafer 200 in step 3 (to be describedlater), or may be set to a pressure equal to or less than the pressurein the process chamber 201 when the chlorosilane-based source gas (HCDSgas) is supplied to the wafer 200 in step 1. That is, theabove-mentioned pressures P₁ to P₃ may be set to satisfy a relation ofP₃≧P₂, and also, may be set to satisfy a relation of P₃, P₁≧P₂.

That is, the carbon concentration in the SiOCN film or the SiOC filmformed by appropriately controlling the pressure in the process chamber201 when the amine-based gas is supplied can be finely adjusted.

A rare gas such as Ar gas, He gas, Ne gas, or Xe gas, in addition to theN₂ gas, may be used as an inert gas.

[Step 3]

O₂ Gas Supply

After step 2 is terminated and the residual gas in the process chamber201 is removed, the valve 243 c of the third gas supply pipe 232 c isopened to flow the O₂ gas into the third gas supply pipe 232 c. A flowrate of the O₂ gas flowing in the third gas supply pipe 232 c isadjusted by the mass flow controller 241 c. The flow rate-adjusted O₂gas is supplied into the process chamber 201 through the gas supply hole250 c of the third nozzle 249 c. The O₂ gas supplied into the processchamber 201 is thermally activated (excited) to be exhausted through theexhaust pipe 231. Here, the thermally activated O₂ gas is supplied tothe wafer 200. Here, at the same time, the valve 243 g is opened to flowthe N₂ gas into the third inert gas supply pipe 232 g. The N₂ gas issupplied into the process chamber 201 with the O₂ gas to be exhaustedthrough the exhaust pipe 231. In addition, here, in order to preventinfiltration of the O₂ gas into the first nozzle 249 a and the secondnozzle 249 b, the valves 243 e and 243 f are opened to flow the N₂ gasinto the first inert gas supply pipe 232 e and the second inert gassupply pipe 232 f. The N₂ gas is supplied into the process chamber 201via the first gas supply pipe 232 a, the second gas supply pipe 232 b,the first nozzle 249 a and the second nozzle 249 b to be exhaustedthrough the exhaust pipe 231.

Here, the APC valve 244 is appropriately adjusted to set the pressure inthe process chamber 201 to a pressure within a range of, for example, 1to 3,000 Pa. As the pressure in the process chamber 201 is set to arelative high pressure range, the O₂ gas can be thermally activated withnon-plasma. In addition, as the O₂ gas is thermally activated andsupplied, a soft reaction can be generated and oxidation (to bedescribed later) can be softly performed. A supply flow rate of the O₂gas controlled by the mass flow controller 241 c is set to a flow ratein a range of, for example, 100 to 10,000 sccm. Supply flow rates of theN₂ gas controlled by the mass flow controllers 241 g, 241 e and 241 fare set to flow rates within a range of, for example, 100 to 10,000sccm. Here, a partial pressure of the O₂ gas in the process chamber 201is set to a pressure within a range of 0.01 to 2,970 Pa. A time ofsupplying the thermally activated O₂ gas to the wafer 200, i.e., a gassupply time (an irradiation time), is set to a time within a range of,for example, 1 to 120 seconds, preferably, 1 to 60 seconds. Here,similar to steps 1 and 2, a temperature of the heater 207 is set suchthat a temperature of the wafer 200 is set to a temperature within arange of, for example, 250 to 700° C., preferably 300 to 650° C., andmore preferably 350 to 600° C.

The gas flowing into the process chamber 201 is the O₂ gas thermallyactivated by increasing the pressure in the process chamber 201, andneither the HCDS gas nor the TEA gas flows into the process chamber 201.Accordingly, the O₂ gas does not generate a gaseous reaction, and theactivated O₂ gas reacts with at least a portion of the first layercontaining Si, N and C formed on the wafer 200 in step 2. Accordingly,the first layer is oxidized to be modified as a layer containingsilicon, oxygen, carbon and nitrogen, i.e., a silicon oxycarbonitridelayer (a SiOCN layer), or a layer containing silicon, oxygen and carbon,i.e., a silicon oxycarbide layer (a SiOC layer), which is a secondlayer.

In addition, as the O₂ gas is thermally activated to flow into theprocess chamber 201, the first layer can be thermally oxidized to bemodified (changed) into a SiOCN layer or a SiOC layer. Here, an Oelement is added to the first layer, and the first layer is modifiedinto the SiOCN layer or the SiOC layer. In addition, here, while Si—Obonding in the first layer is increased by an action of the thermaloxidation due to the O₂ gas, Si—N bonding, Si—C bonding and Si—Sibonding are reduced to reduce a ratio of the N element, a ratio of the Celement, and a ratio of the Si element in the first layer. Here, as thethermal oxidation time is extended or an oxidation power of the thermaloxidation is increased, most of the N element can be eliminated toreduce the N element to an impurity level, or the N element can becomesubstantially extinct. That is, the first layer can be modified into theSiOCN layer or the SiOC layer while varying the composition ratio in adirection of increasing the oxygen concentration or a direction ofreducing the nitrogen concentration, the carbon concentration and thesilicon concentration. Here, since a ratio of the O element in the SiOCNlayer or the SiOC layer, i.e., the oxygen concentration, can be finelyadjusted by controlling the processing conditions such as the pressurein the process chamber 201 or the gas supply time, the composition ratioof the SiOCN layer or the SiOC layer can be more accurately controlled.

In addition, it is determined that the C element in the first layerformed in steps 1 and 2 is richer than the N element. For example, insome experiments, the carbon concentration may be twice the nitrogenconcentration or more. That is, before the N element in the first layeris completely eliminated by the action of the thermal oxidation due tothe O₂ gas, i.e., as the oxidation is prevented while the N elementremains, the C element and the N element remain in the first layer andthe first layer is modified into the SiOCN layer. In addition, even whenelimination of most of the N element in the first layer is terminated bythe action of the thermal oxidation due to the O₂ gas, the C elementremains in the first layer, and the first layer is modified into theSiOC layer by preventing the oxidation in this state. That is, the ratioof the C element, i.e., the carbon concentration, can be controlled bycontrolling the gas supply time (an oxidation processing time) or theoxidation power, and any one of the SiOCN layer and the SiOC layer canbe formed while controlling the composition ratio. In addition, here,since a ratio of the O element, i.e., the oxygen concentration, in theSiOCN layer or the SiOC layer can be finely adjusted by controlling theprocessing conditions such as the pressure in the process chamber 201 orthe gas supply time, the composition ratio of SiOCN layer or the SiOClayer can be more accurately controlled.

In addition, here, the oxidation reaction of the first layer may not besaturated. For example, when the first layer having a thickness of lessthan one atomic layer to several atomic layers is formed in steps 1 and2, a portion of the first layer may be oxidized. In this case, theoxidation is performed under the conditions in which the oxidationreaction of the first layer is unsaturated such that the entire firstlayer having a thickness of less than one atomic layer to several atomiclayers is not oxidized.

In addition, while the processing conditions in step 3 may be theabove-mentioned processing conditions to make the oxidation reaction ofthe first layer unsaturated, if the processing conditions in step 3 areset to the following processing conditions, the oxidation reaction ofthe first layer is likely to be unsaturated.

Wafer temperature: 500 to 650° C.

Pressure in process chamber: 133 to 2,666 Pa

O₂ gas partial pressure: 33 to 2,515 Pa

O₂ gas supply flow rate: 1,000 to 5,000 sccm

N₂ gas supply flow rate: 300 to 3,000 sccm

O₂ gas supply time: 6 to 60 seconds

Removal of Residual Gas

After the second layer is formed, the valve 243 c of the third gassupply pipe 232 c is closed to stop supply of the O₂ gas. Here, theinside of the process chamber 201 is vacuum-exhausted by the vacuum pump246 in a state in which the APC valve 244 of the exhaust pipe 231 isopen, and the O₂ gas or reaction byproduct remaining in the processchamber 201 after non-reaction or contribution to formation of thesecond layer is removed from the process chamber 201. In addition, here,supply of the N₂ gas into the process chamber 201 is maintained in astate in which the valves 243 g, 243 e and 243 f are open. The N₂ gasacts as a purge gas, and thus the O₂ gas or reaction byproduct remainingin the process chamber 201 after non-reaction or contribution toformation of the second layer can be effectively removed from theprocess chamber 201.

In addition, here, the gas remaining in the process chamber 201 may notbe completely removed, and the inside of the process chamber 201 may notbe completely purged. When the amount of gas remaining in the processchamber 201 is very small, there is no bad affect generated in step 1performed thereafter. Here, the flow rate of the N₂ gas supplied intothe process chamber 201 need not be set to be a large flow rate, and forexample, as the amount of N₂ gas is supplied to a level similar to acapacity of the reaction tube 203 (the process chamber 201), the purgecan be performed such that a bad effect is not generated in step 1. Asdescribed above, as the inside of the process chamber 201 is notcompletely purged, the purge time can be reduced to improve throughput.In addition, consumption of the N₂ gas can also be suppressed to minimalnecessity.

Nitrous oxide (N₂O) gas, nitrogen monoxide (NO) gas, nitrogen dioxide(NO₂) gas, ozone (O₃) gas, hydrogen (H₂) gas+oxygen (O₂) gas, H₂ gas+O₃gas, steam (H₂O) gas, carbon monoxide (CO) gas, carbon dioxide (CO₂)gas, and so on, may be used as the oxygen-containing gas, in addition tothe O₂ gas. A rare gas such as Ar gas, He gas, Ne gas, Xe gas, and soon, may be used as the inert gas, in addition to the N₂ gas.

Performing Predetermined Number of Times

The above-mentioned steps 1 to 3 may be set as one cycle and the cyclemay be performed once or more (a predetermined number of times) to forma film containing silicon, oxygen, carbon and nitrogen having apredetermined composition and a predetermined film thickness, i.e., asilicon oxycarbonitride film (a SiOCN film), or a film containingsilicon, oxygen and carbon, i.e., a silicon oxycarbide film (a SiOCfilm), on the wafer 200. In addition, the above-mentioned cycle may beperformed a plurality of times. That is, the thickness of the SiOCNlayer or the SiOC layer formed at each unit cycle may be set to besmaller than a desired film thickness, and the cycle may be repeated aplurality of times to the desired film thickness.

In addition, when the cycle is performed a plurality of times, thephrase “a predetermined gas is supplied to the wafer 200” in each stepafter at least two cycles means “a predetermined gas is supplied to alayer formed on the wafer 200, i.e., the uppermost surface of the wafer200, which is a stacked body,” and the phrase “a predetermined layer isformed on the wafer 200” means “a predetermined layer is formed on alayer formed on the wafer 200, i.e., the uppermost surface of the wafer200, which is a stacked body.” This is similar to the above. Inaddition, the above-mentioned matters are similar in the respectivevariants and the other embodiments.

Purge and Return to Atmospheric Pressure

When film-forming processing of forming the SiOCN film or the SiOC filmof a predetermined film thickness having a predetermined composition isperformed, the valves 243 e, 243 f and 243 g are opened to supply the N₂gas, which is an inert gas, into the process chamber 201 through thefirst inert gas supply pipe 232 e, the second inert gas supply pipe 232f and the third inert gas supply pipe 232 g to be exhausted through theexhaust pipe 231. The N₂ gas acts as a purge gas, and thus the inside ofthe process chamber 201 is purged with the inert gas so that the gas orreaction byproduct remaining in the process chamber 201 is removed fromthe process chamber 201 (purge). After that, atmosphere in the processchamber 201 is substituted with the inert gas (substitution of the inertgas), and the pressure in the process chamber 201 is returned to anormal pressure (return to atmospheric pressure).

Boat Unloading and Wafer Discharging

After that, the seal cap 219 is lowered by the boat elevator 115 to openthe lower end of the reaction tube 203, and the processed wafer 200supported by the boat 217 is unloaded to the outside of the reactiontube 203 through the lower end of the reaction tube 203 (boatunloading). Then, the processed wafer 200 is discharged by the boat 217(wafer discharging).

(3) Effects According to the Embodiment

According to the embodiment, one or a plurality of effects are providedas described below.

(a) According to the embodiment, steps 1 and 2 are alternately performedonce to form the first layer containing Si, N and C, and then step 3 ofsupplying the O₂ gas, which is an oxygen-containing gas, as a secondreactive gas to oxidize the first layer to be modified into the SiOCNlayer or the SiOC layer, which is a second layer, is performed so that acomposition ratio of oxygen, carbon and nitrogen in the formed SiOCNfilm or SiOC film can be adjusted. In addition, here, as the O₂ gas isthermally activated and supplied, Si—O bonding in the SiOCN film or theSiOC film can be increased by the action of the thermal oxidation, andSi—C bonding, Si—N bonding and Si—Si bonding can be reduced. That is,the composition ratio can be varied in a direction of increasing theoxygen concentration or in a direction of reducing the nitrogenconcentration, the carbon concentration and the silicon concentration.In addition, here, the composition ratio can be varied by extending thethermal oxidation time or increasing the oxidation power of the thermaloxidation in a direction of increasing the oxygen concentration or in adirection of further reducing the nitrogen concentration, the carbonconcentration and the silicon concentration. Further, here, since theprocessing conditions such as the pressure in the process chamber 201 orthe gas supply time can be controlled to finely adjust a ratio of the Oelement in the SiOCN film or the SiOC film, i.e., the oxygenconcentration, the composition ratio of the SiOCN film or the SiOC filmcan be more accurately controlled. Accordingly, permittivity of theformed SiOCN film or SiOC film can be adjusted, an etching resistancecan be improved, or a leak resistance can be improved.

(b) According to the embodiment, the carbon concentration in the SiOCNfilm or the SiOC film can be increased using the amine-based gascontaining the three elements including carbon, nitrogen and hydrogenand having a composition wherein the number of carbon atoms is greaterthan that of nitrogen atoms in one molecule as the first reactive gas.

In particular, the carbon concentration in the SiOCN film or the SiOCfilm can be increased using the amine-based gas containing a pluralityof ligands containing a carbon (C) atom in one molecule, i.e., theamine-based gas containing a plurality of hydrocarbon groups such asalkyl groups in one molecule as the first reactive gas. Specifically,the carbon concentration in the SiOCN film or the SiOC film can beincreased using TEA gas, TMA gas, TPA gas, TIPA gas, TBA gas or TIBA gascontaining three ligands (hydrocarbon groups such as alkyl groups)containing a carbon (C) atom in one molecule, or DEA gas, DMA gas, DPAgas, DIPA gas, DBA gas or DMA gas containing two ligands (hydrocarbongroups such as alkyl groups) containing a carbon (C) atom in onemolecule as the first reactive gas.

(c) According to the embodiment, a cycle rate (a thickness of the SiOCNlayer or the SiOC layer formed at each unit cycle) or the nitrogenconcentration or the carbon concentration in the SiOCN film or the SiOCfilm can be finely adjusted by the number of ligands (the number ofhydrocarbon groups such as alkyl groups) containing a carbon atomcontained in the first reactive gas, i.e., appropriately changing a gasspecies of the first reactive gas.

For example, the cycle rate can be improved and the ratio of thenitrogen concentration with respect to the carbon concentration in theSiOCN film or the SiOC film (the ratio of the nitrogen concentration/thecarbon concentration) can be increased using the amine-based gas, whichis the first reactive gas, containing two ligands (hydrocarbon groupssuch as alkyl groups) containing a carbon atom in one molecule such asDEA gas, in comparison with the case using the amine-based gascontaining three ligands (hydrocarbon groups such as alkyl groups)containing a carbon (C) atom in one molecule such as TEA gas.

In addition, for example, the ratio of the carbon concentration withrespect to the nitrogen concentration in the SiOCN film or the SiOC film(the ratio of the carbon concentration/the nitrogen concentration) canbe increased using the amine-based gas, which is the first reactive gas,containing three ligands (hydrocarbon groups such as alkyl groups)containing a carbon atom in one molecule such as TEA gas, in comparisonwith the case using the amine-based gas containing two ligands(hydrocarbon groups such as alkyl groups) containing a carbon atom inone molecule such as DEA gas.

(d) According to the embodiment, the carbon concentration in the SiOCNfilm or the SiOC film can be finely adjusted by controlling the pressurein the process chamber 201 when the first reactive gas is supplied.

For example, as the pressure in the process chamber 201 when the TEA gasis supplied to the wafer 200 in step 2 is higher than the pressure inthe process chamber 201 when the HCDS gas is supplied to the wafer 200in step 1, the carbon concentration in the SiOCN film or the SiOC filmcan be further increased. In addition, as the pressure in the processchamber 201 when the TEA gas is supplied to the wafer 200 is higher thanthe pressure in the process chamber 201 when the O₂ gas is supplied tothe wafer 200 in step 3, the carbon concentration in the SiOCN film orthe SiOC film can be further increased.

In addition, for example, an increment of the carbon concentration inthe SiOCN film or the SiOC film can be appropriately suppressed bysetting the pressure in the process chamber 201 when the TEA gas issupplied to the wafer 200 in Step 2 to a pressure equal to or less thanthe pressure in the process chamber 201 when the O₂ gas is supplied tothe wafer 200 in step 3, or to a pressure equal to or less than thepressure in the process chamber 201 when the HCDS gas is supplied to thewafer 200 in step 1.

(e) According to the embodiment, reaction controllability, inparticular, composition controllability, upon formation of the SiOCNfilm or the SiOC film can be improved using the TEA gas as the firstreactive gas, which is an amine-based gas, containing the three elementsincluding carbon, nitrogen and hydrogen and containing no silicon and nometal. That is, in the film-forming sequence of the embodiment using theTEA gas as the first reactive gas, in comparison with the film-formingsequence using tetrakis ethyl methyl aminohafnium (Hf[N(C₂H₅)(CH₃)]₄,abbreviation: TEMAH) gas containing the four elements hafnium, carbon,nitrogen and hydrogen, which is the first reactive gas, reactioncontrollability, in particular, composition controllability, when thefirst layer is formed by reacting the first reactive gas with thesilicon-containing layer containing Cl can be improved. Accordingly,composition control of the SiOCN film or the SiOC film can be easilyperformed.

(f) According to the embodiment, an impurity concentration in the formedSiOCN film or the SiOC film can be reduced using the TEA gas as thefirst reactive gas, which is an amine-based gas, containing the threeelements including carbon, nitrogen and hydrogen and containing nosilicon and no metal. That is, in the film-forming sequence of theembodiment using the TEA gas as the first reactive gas, in comparisonwith the film-forming sequence using TEMAH gas containing the fourelements hafnium, carbon, nitrogen and hydrogen as the first reactivegas, mixing probability of an impurity element into the first layerformed by a reaction of the first reactive gas with thesilicon-containing layer containing Cl can be reduced, and an impurityconcentration in the formed SiOCN film or SiOC film can be reduced.

(g) According to the embodiment, film thickness uniformity in a surfaceof the wafer 200 and between surfaces of the wafers 200 of the SiOCNfilm or the SiOC film can be improved using the TEA gas as the firstreactive gas, which is the amine-based gas containing the three elementsincluding carbon, nitrogen and hydrogen and containing no silicon and nometal. That is, since the TEA gas containing the three elementsincluding carbon, nitrogen and hydrogen has high reactivity with respectto the silicon-containing layer containing Cl in comparison with theTEMAH gas containing four elements, for example, hafnium, carbon,nitrogen and hydrogen, the film-forming sequence of the embodiment usingthe TEA gas as the first reactive gas can securely and uniformly performa reaction of the first reactive gas with the silicon-containing layercontaining Cl throughout a surface of the wafer 200 and between surfacesof the wafers 200. As a result, film thickness uniformity in a surfaceof the wafer 200 and between surfaces of the wafers 200 in the SiOCNfilm or the SiOC film can be improved.

Variants

While an example in which steps 1 to 3 are set as one cycle and thecycle is performed a predetermined number of times in theabove-mentioned film-forming sequence of FIGS. 4 and 5 has beendescribed, the film-forming sequence according to the present inventionis not limited thereto but may be varied as described below.

For example, like variant 1 shown in FIG. 6A, steps 1 and 2 may be setas one set and after the set is performed a predetermined number oftimes (m times), step 3 may be performed, and the above may be set asone cycle and the cycle may be performed a predetermined number of times(n times). That is, a cycle including a process in which a process ofsupplying a chlorosilane-based source gas (HCDS gas) to the wafer 200 inthe process chamber 201 and a process of supplying an amine-based gas(TEA gas) containing the three elements including carbon, nitrogen andhydrogen and having a composition wherein the number of carbon atoms isgreater than that of nitrogen atoms to the wafer 200 in the processchamber 201 are alternately performed a predetermined number of times (mtimes) to form a first layer containing silicon, nitrogen and carbon onthe wafer 200; and a process of supplying an oxygen-containing gas (O₂gas) to the wafer 200 in the process chamber 201 to modify the firstlayer to form a SiOCN layer or a SiOC layer as a second layer; may beperformed a predetermined number of times (n times) to form a SiOCN filmor a SiOC film having a predetermined composition and a predeterminedfilm thickness on the wafer 200. In addition, the phrase “performed apredetermined number of times” means “performed one or a plurality oftimes, i.e., performed once or more.” FIG. 6A shows an example in whicha set of steps 1 and 2 is performed twice per cycle, i.e., an example inwhich a process of performing a set of steps 1 and 2 twice and a processof performing step 3 are set as one cycle and the cycle is performed apredetermined number of times (n times). The variant is distinguishedfrom the above-mentioned film-forming sequence shown in FIGS. 4 and 5 inthat the set of steps 1 and 2 is performed a predetermined number oftimes (m times) and then step 3 is performed, and the above is set asone cycle, while everything else is similar to the above-mentionedfilm-forming sequence. In addition, the case in which the number oftimes m the set of steps 1 and 2 is performed in the variant is set asone corresponds to the above-mentioned film-forming sequence shown inFIGS. 4 and 5.

In addition, for example, like variant 2 shown in FIG. 6B, steps 1, 2, 1and 3 may be sequentially performed as one cycle and the cycle may beperformed a predetermined number of times (n times). That is, a cycleincluding a process in which a process of supplying a chlorosilane-basedsource gas (HCDS gas) to the wafer 200 in the process chamber 201 and aprocess of supplying an amine-based gas (TEA gas) containing the threeelements including carbon, nitrogen and hydrogen and having acomposition wherein the number of carbon atoms is greater than that ofnitrogen atoms to the wafer 200 in the process chamber 201 arealternately performed once to form a first layer containing silicon,nitrogen and carbon on the wafer 200; and a process in which a processof supplying a chlorosilane-based source gas (HCDS gas) to the wafer 200in the process chamber 201 and a process of supplying anoxygen-containing gas (O₂ gas) to the wafer 200 in the process chamber201 are alternately performed once to form a silicon oxide layer (a SiOlayer) on the first layer as a second layer; may be performed apredetermined number of times (n times) to form a SiOCN film having apredetermined composition and a predetermined film thickness formed byalternately depositing the first layer and the second layer on the wafer200. In addition, the variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 4 and 5 in that steps 1, 2, 1 and 3are set as one cycle, while everything else is similar to theabove-mentioned film-forming sequence.

In addition, for example, like variant 3 shown in FIG. 6C, after steps 1and 2 are set as one set and the set is performed a predetermined numberof times (m times), steps 1 and 3 may be set as one set and the set maybe performed a predetermined number of times (m′ times), and thecombination may be set as one cycle and the cycle may be performed apredetermined number of times (n times). That is, a cycle including aprocess in which a process of supplying a chlorosilane-based source gas(HCDS gas) to the wafer 200 in the process chamber 201 and a process ofsupplying an amine-based gas (TEA gas) containing the three elementsincluding carbon, nitrogen and hydrogen and having a composition whereinthe number of carbon atoms is greater than that of nitrogen atoms to thewafer 200 in the process chamber 201 are alternately performed apredetermined number of times (m times) to form a first layer containingsilicon, nitrogen and carbon on the wafer 200; and a process in which aprocess of supplying a chlorosilane-based source gas (HCDS gas) to thewafer 200 in the process chamber 201 and a process of supplying anoxygen-containing gas (O₂ gas) to the wafer 200 in the process chamber201 are alternately performed a predetermined number of times (m′ times)to form a SiO layer on the first layer as a second layer; may beperformed a predetermined number of times (n times) to form a SiOCN filmhaving a predetermined composition and a predetermined film thicknessformed by alternately depositing the first layer and the second layer onthe wafer 200. FIG. 6C shows an example in which a set of steps 1 and 2and a set of steps 1 and 3 are performed twice per cycle, i.e., anexample in which a process of performing a set of steps 1 and 2 twiceand a process of performing a set of steps 1 and 3 twice are set as onecycle and the cycle is performed a predetermined number of times (ntimes). In addition, the variant is distinguished from theabove-mentioned film-forming sequence shown in FIGS. 4 and 5 in thatafter a set of steps 1 and 2 is performed a predetermined number oftimes (m times), a set of steps 1 and 3 is performed a predeterminednumber of times (m′ times), and the above is set as one cycle, whileeverything else is similar to the above-mentioned film-forming sequence.In addition, the case in which the number of times m the set of steps 1and 2 is performed in the variant is one and the number of times m′ theset of steps 1 and 3 is performed is one corresponds to the film-formingsequence of variant 2 shown in FIG. 6B.

Even in this variant, effects similar to the above-mentionedfilm-forming sequence shown in FIGS. 4 and 5 will be provided. Inaddition, according to the above-mentioned variant, a ratio of a siliconelement, a nitrogen element, a carbon element and an oxygen element inthe SiOCN film or the SiOC film can be more accurately controlled, andcontrollability of the composition ratio of the SiOCN film or the SiOCfilm can be improved.

For example, an absolute amount of the silicon element, the nitrogenelement and the carbon element of the first layer can be increased byincreasing the number m of sets including step 1 and step 2 in variant1, a ratio of the silicon element, the nitrogen element and the carbonelement with respect to the oxygen element of the SiOCN layer or theSiOC layer can be controlled to be increased as the first layer in whichabsolute amounts of the respective elements are increased is oxidized instep 3, and a ratio of the silicon element, the nitrogen element and thecarbon element with respect to the oxygen element of the finally formedSiOCN film or SiOC film can be controlled to be increased.

In addition, for example, an absolute amount of the silicon element, thenitrogen element and the carbon element of the first layer can bereduced by reducing the number m of sets including step 1 and step 2 invariant 1, a ratio of the silicon element, the nitrogen element and thecarbon element with respect to the oxygen element of the SiOCN layer orthe SiOC layer can be controlled to be decreased as the first layer inwhich absolute amounts of the respective elements are decreased isoxidized in step 3, and a ratio of the silicon element, the nitrogenelement and the carbon element with respect to the oxygen element of thefinally formed SiOCN film or SiOC film can be controlled to bedecreased.

Even in variants 2 and 3, a ratio of the silicon element, the nitrogenelement, the carbon element and the oxygen element in the SiOCN film orthe SiOC film can be more accurately controlled according to the sameprinciple.

In addition, according to the variants, since the thickness formed inone cycle can be increased, the cycle rate (the thickness of the SiOCNlayer or the SiOC layer formed in each unit cycle) can be improved. Inaddition, the film-forming rate can also be improved.

For example, as the number m of sets including step 1 and step 2 isincreased in variants 1 and 3, the number of layers of the first layerformed in one cycle, i.e., the thickness of the first layer formed inone cycle, can be increased by the set number m, and the cycle rate canbe improved. In addition, as the number m′ of sets including step 1 andstep 3 is increased in variant 3, the number of layers of the SiO layer,which is the second layer, formed in one cycle, i.e., the thickness ofthe second layer formed in one cycle, can be increased by the set numberm′, and thus the cycle rate can be improved. Further, since step 1 isperformed twice per cycle in variant 2, the cycle rate can also beimproved even in variant 2. In addition, the film-forming rate can alsobe improved.

In addition, in variants 2 and 3, a sequence of the process of formingthe first layer containing Si, N and C and the process of forming theSiO layer as the second layer may be changed. That is, after the processof forming the second layer (the SiO layer), the process of forming thefirst layer may be performed, and the above may be set as one cycle. Inaddition, such a variant may be arbitrarily combined and used.

Second Embodiment of the Invention

Next, a second embodiment of the present invention will be described.

In the above-mentioned first embodiment, while an example in which thesilicon oxycarbonitride film or the silicon oxycarbide film having apredetermined composition and a predetermined film thickness is formedon the wafer 200 using the oxygen-containing gas (O₂ gas) as the secondreactive gas has been described, in the embodiment, an example in whicha silicon carbonitride film having a predetermined composition and apredetermined film thickness is formed on the wafer 200 using anitrogen-containing gas (NH₃ gas) as the second reactive gas will bedescribed.

That is, in the embodiment, an example in which a cycle including aprocess in which a process of supplying HCDS gas, which is achlorosilane-based source gas, to the wafer 200 in the process chamber201 as a source gas and a process of supplying TEA gas, which is anamine-based gas containing a plurality of (three) ligands (ethyl groups)containing a carbon atom in one molecule to the wafer 200 in the processchamber 201 as a first reactive gas containing the three elementsincluding carbon, nitrogen and hydrogen and having a composition whereinthe number of carbon atoms is greater than that of nitrogen atoms in onemolecule are alternately performed once to form a first layer containingsilicon, nitrogen and carbon on the wafer 200; and a process ofsupplying NH₃ gas, which is a nitrogen-containing gas (a nitriding gas),to the wafer 200 in the process chamber 201 as a second reactive gasdifferent from the source gas and the first reactive gas to modify thefirst layer to form a silicon carbonitride layer (a SiCN layer) as asecond layer; is performed a predetermined number of times (n times) toform a silicon carbonitride film (a SiCN film) having a predeterminedcomposition and a predetermined film thickness on the wafer 200.

FIG. 7 is a view showing a film-forming flow of the embodiment. FIG. 8is a view showing a gas supply timing in a film-forming sequence of theembodiment. In addition, the embodiment is distinguished from the firstembodiment in that the thermally activated NH₃ gas is used as the secondreactive gas in step 3, and everything else is similar to the firstembodiment. Hereinafter, step 3 of the embodiment will be described.

[Step 3]

NH₃ Gas Supply

After step 2 is terminated and the residual gas in the process chamber201 is removed, the valve 243 d of the fourth gas supply pipe 232 d isopened to flow NH₃ gas into the fourth gas supply pipe 232 d. A flowrate of the NH₃ gas flowing in the fourth gas supply pipe 232 d isadjusted by the mass flow controller 241 d. The flow rate-adjusted NH₃gas is supplied into the process chamber 201 through the gas supply hole250 c of the third nozzle 249 c. The NH₃ gas supplied into the processchamber 201 is thermally activated (excited) to be exhausted through theexhaust pipe 231. Here, the thermally activated NH₃ gas is supplied tothe wafer 200. At the same time, the valve 243 g is opened to flow N₂gas into the third inert gas supply pipe 232 g. The N₂ gas is suppliedinto the process chamber 201 with the NH₃ gas to be exhausted throughthe exhaust pipe 231. In addition, here, in order to preventinfiltration of the NH₃ gas into the first nozzle 249 a and the secondnozzle 249 b, the valves 243 e and 243 f are opened to flow the N₂ gasinto the first inert gas supply pipe 232 e and the second inert gassupply pipe 232 f. The N₂ gas is supplied into the process chamber 201via the first gas supply pipe 232 a, the second gas supply pipe 232 b,the first nozzle 249 a and the second nozzle 249 b to be exhaustedthrough the exhaust pipe 231.

Here, the APC valve 244 is appropriately adjusted to set the pressure inthe process chamber 201 to a pressure within a range of, for example, 1to 3,000 Pa. As the pressure in the process chamber 201 is set to arelatively high pressure, the NH₃ gas can be thermally activated withnon-plasma. In addition, the NH₃ gas can be thermally activated andsupplied to cause a soft reaction, and thus, nitridation (to bedescribed later) can be softly performed. A supply flow rate of the NH₃gas controlled by the mass flow controller 241 c is set to a flow ratewithin a range of, for example, 100 to 10,000 sccm. Supply flow rates ofthe N₂ gas controlled by the mass flow controllers 241 g, 241 e and 241f are set to flow rates within a range of, for example, 100 to 10,000sccm. Here, a partial pressure of the NH₃ gas in the process chamber 201is set to a pressure within a range of 0.01 to 2,970 Pa. A time forsupplying the thermally activated NH₃ gas to the wafer 200, i.e., a gassupply time (an irradiation time), is set to a time within a range of,for example, 1 to 120 seconds, preferably, 1 to 60 seconds. Here,similar to steps 1 to 2, a temperature of the heater 207 is set suchthat the temperature of the wafer 200 is set to a temperature within arange of, for example, 250 to 700° C., preferably 300 to 650° C., morepreferably 350 to 600° C.

Here, the gas flowing in the process chamber 201 is the NH₃ gasthermally activated by increasing the pressure in the process chamber201, and neither the HCDS gas nor the TEA gas flows in the processchamber 201. Accordingly, the NH₃ gas does not generate a gaseousreaction, and the activated NH₃ gas reacts at least a portion of thefirst layer containing Si, N and C formed on the wafer 200 in step 2.Accordingly, the first layer is nitrided to be modified into a layercontaining silicon, carbon and nitrogen, i.e., a silicon carbonitridelayer (a SiCN layer) as a second layer.

In addition, as the NH₃ gas is thermally activated to flow in theprocess chamber 201, the first layer can be thermally nitrided to bemodified (changed) into a SiCN layer. Here, the first layer is modifiedinto the SiCN layer while increasing a ratio of an N element in thefirst layer. Meanwhile, here, Si—N bonding in the first layer isincreased by an action of thermal nitridation due to the NH₃ gas, andSi—C bonding and Si—Si bonding are reduced to reduce a ratio of a Celement and a ratio of a Si element in the first layer. That is, thefirst layer can be modified into the SiCN layer while varying thecomposition ratio in a direction of increasing the nitrogenconcentration or a direction of reducing the carbon concentration andthe silicon concentration. Further, here, the ratio of the N element inthe SiCN layer, i.e., the nitrogen concentration, can be finely adjustedby controlling the processing conditions such as the pressure in theprocess chamber 201 or the gas supply time, and the composition ratio ofthe SiCN layer can be more accurately controlled.

In addition, here, the nitridation reaction of the first layer may notbe saturated. For example, when the first layer having a thickness ofless than one atomic layer to several atomic layers is formed in steps 1and 2, a portion of the first layer may be nitrided. In this case, thenitridation is performed under the conditions in which the nitridationreaction of the first layer is unsaturated, such that the entire firstlayer having a thickness of less than one atomic layer to several atomiclayers is not nitrided.

Further, while the processing conditions in step 3 are set to theabove-mentioned processing conditions to make the nitridation reactionof the first layer unsaturated, the nitridation of the first layer caneasily become unsaturated by setting the processing conditions in step 3to the following processing conditions.

Wafer temperature: 500 to 650° C.

Pressure in process chamber: 133 to 2,666 Pa

NH₃ gas partial pressure: 33 to 2,515 Pa

NH₃ gas supply flow rate: 1,000 to 5,000 sccm

N₂ gas supply flow rate: 300 to 3,000 sccm

NH₃ gas supply time: 6 to 60 seconds

Removal of Residual Gas

After the second layer is formed, the valve 243 d of the fourth gassupply pipe 232 d is closed to stop supply of the NH₃ gas. Here, in astate in which the APC valve 244 of the exhaust pipe 231 is open, theinside of the process chamber 201 is vacuum-exhausted by the vacuum pump246 to remove the NH₃ gas or reaction byproduct remaining in the processchamber 201 after non-reaction or contribution to formation of thesecond layer from the process chamber 201. In addition, here, the valves243 g, 243 e and 243 f are opened to maintain supply of the N₂ gas intothe process chamber 201. The N₂ gas acts as a purge gas, and thus theNH₃ gas or reaction byproduct remaining in the process chamber 201 afternon-reaction or contribution to formation of the second layer can beeffectively removed from the process chamber 201.

In addition, here, the gas remaining in the process chamber 201 may notbe completely removed, and the inside of the process chamber 201 may notbe completely purged. When the amount of gas remaining in the processchamber 201 is very small, there is no bad effect generated in step 1performed thereafter. Here, a flow rate of the N₂ gas supplied into theprocess chamber 201 need not be set a large flow rate, and for example,as the amount of N₂ gas similar to a capacity of the reaction tube 203(the process chamber 201) is supplied, the purge can be performed not togenerate the bad effect in step 1. As described above, as the inside ofthe process chamber 201 is not completely purged, the purge time can bereduced to improve throughput. In addition, consumption of the N₂ gascan be suppressed to minimal necessity.

A gas containing diazene (N₂H₂) gas, hydrazine (N₂H₄) gas, N₃H₈ gas, ora compound thereof may be used as the nitrogen-containing gas, inaddition to the NH₃ gas. A rare gas such as Ar gas, He gas, Ne gas or Xegas may be used as the inert gas, in addition to the N₂ gas.

Performing Predetermined Number of Times

The above-mentioned steps 1 to 3 may be set as one cycle, and the cyclemay be performed once or more (a predetermined number of times) to forma film containing silicon, carbon and nitrogen and having apredetermined composition and a predetermined film thickness, i.e., asilicon carbonitride film (a SiCN film), on the wafer 200. In addition,the above-mentioned cycle may be performed a plurality of times. Thatis, as the thickness of the SiCN layer formed by one cycle is set to besmaller than a desired film thickness, the above-mentioned cycle may berepeated a plurality of times to a desired film thickness.

According to the embodiment, after steps 1 and 2 are alternatelyperformed once to form the first layer containing Si, N and C, step 3 ofsupplying the NH₃ gas, which is a nitrogen-containing gas, as the secondreactive gas to nitride the first layer to modify the SiCN layer, whichis a second layer, may be performed to adjust the composition ratio ofcarbon and nitrogen in the formed SiCN film. In addition, here, as theNH₃ gas is thermally activated and supplied, Si—N bonding in the SiCNfilm can be increased by an action of thermal nitridation, and Si—Cbonding and Si—Si bonding can also be reduced. That is, the compositionratio can be varied in a direction of increasing the nitrogenconcentration and in a direction of reducing the carbon concentrationand the silicon concentration. In addition, here, as a thermalnitridation time is extended or a nitridation power in thermalnitridation is improved, the composition ratio can be varied in adirection of further increasing the nitrogen concentration and in adirection of further reducing the carbon concentration and the siliconconcentration. Further, here, as the processing conditions such as thepressure in the process chamber 201 or the gas supply time arecontrolled, a ratio of the N element in the SiCN film, i.e., thenitrogen concentration, can be finely adjusted, and the compositionratio of the SiCN film can be more accurately controlled. Accordingly,permittivity of the formed SiCN film can be adjusted, an etchingresistance can be improved, or a leak resistance can be improved.

In addition, according to the embodiment, effects similar to theabove-mentioned first embodiment are provided. That is, by using the TEAgas, which is an amine-based gas containing the three elements includingcarbon, nitrogen and hydrogen, having a composition wherein the numberof carbon atoms is greater than that of nitrogen atoms, and containingno silicon and no metal as the first reactive gas, the carbonconcentration in the SiCN film can be increased, reactioncontrollability, in particular, composition controllability, uponformation of the SiCN film can be improved, an impurity concentration inthe film can be reduced, or film thickness uniformity in a surface ofthe wafer 200 and between surfaces of the wafers 200 can be improved.

(4) Variant

While an example in which steps 1 to 3 are set as one cycle and thecycle is performed a predetermined number of times has been described inthe above-mentioned film-forming sequence shown in FIGS. 7 and 8, thefilm-forming sequence according to the embodiment is not limited theretobut may be varied as described below.

For example, like variant 1 shown in FIG. 9A, after steps 1 and 2 areset as one set and the one set is performed a predetermined number oftimes (m times), step 3 may be performed, the above may be set as onecycle, and the cycle may be performed a predetermined number of times (ntimes). That is, a cycle including a process in which a process ofsupplying a chlorosilane-based source gas (HCDS gas) to the wafer 200 inthe process chamber 201 and a process of supplying an amine-based gas(TEA gas) containing the three elements including carbon, nitrogen andhydrogen and having a composition wherein the number of carbon atoms isgreater than that of nitrogen atoms to the wafer 200 in the processchamber 201 are alternately performed a predetermined number of times (mtimes) to form a first layer containing silicon, nitrogen and carbon onthe wafer 200; and a process of supplying a nitrogen-containing gas (NH₃gas) to the wafer 200 in the process chamber 201 to modify the firstlayer to form a SiCN layer as a second layer; may be performed apredetermined number of times (n times) to form a SiCN film having apredetermined composition and a predetermined film thickness on thewafer 200. FIG. 9A shows an example in which a set of steps 1 and 2 isperformed twice per cycle, i.e., an example in which a process ofperforming a set of steps 1 and 2 twice and a process of performing step3 are set as one cycle and the cycle is performed a predetermined numberof times (n times). The variant is distinguished from theabove-mentioned film-forming sequence shown in FIGS. 7 and 8 in that aset of steps 1 and 2 is performed a predetermined number of times (mtimes) and then step 3 is performed, and the above is set as one cycle,while everything else is similar to the above-mentioned film-formingsequence. In addition, the case in which the number of times m the setof steps 1 and 2 is performed is one in the variant corresponds to theabove-mentioned film-forming sequence shown in FIGS. 7 and 8.

In addition, for example, like variant 2 shown in FIG. 9B, steps 1, 2, 1and 3 may be sequentially performed as one cycle and the cycle may beperformed a predetermined number of times (n times). That is, a cycleincluding a process in which a process of supplying a chlorosilane-basedsource gas (HCDS gas) to the wafer 200 in the process chamber 201 and aprocess of supplying an amine-based gas (TEA gas) containing the threeelements including carbon, nitrogen and hydrogen and having acomposition wherein the number of carbon atoms is greater than that ofnitrogen atoms to the wafer 200 in the process chamber 201 arealternately performed once to form a first layer containing silicon,nitrogen and carbon on the wafer 200; and a process in which a processof supplying a chlorosilane-based source gas (HCDS gas) to the wafer 200in the process chamber 201 and a process of supplying anitrogen-containing gas (NH₃ gas) to the wafer 200 in the processchamber 201 are alternately performed once to form a silicon nitridelayer (SiN layer) as a second layer on the first layer; may be performeda predetermined number of times (n times) to form a SiCN film having apredetermined composition and a predetermined film thickness formed byalternately depositing the first layer and the second layer on the wafer200. In addition, the variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 7 and 8 in that steps 1, 2, 1 and 3are set as one cycle, and everything else is similar to theabove-mentioned film-forming sequence.

In addition, for example, like variant 3 shown in FIG. 9C, after steps 1and 2 are set as one set and the set is performed a predetermined numberof times (m times), steps 1 and 3 may be set as one set and the set maybe performed a predetermined number of times (m′ times), and thecombinations may be set as one cycle and the cycle may be performed apredetermined number of times (n times). That is, a cycle including aprocess in which a process of supplying a chlorosilane-based source gas(HCDS gas) to the wafer 200 in the process chamber 201 and a process ofsupplying an amine-based gas (TEA gas) containing the three elementsincluding carbon, nitrogen and hydrogen and having a composition whereinthe number of carbon atoms is greater than that of nitrogen atoms to thewafer 200 in the process chamber 201 are alternately performed apredetermined number of times (m times) to form a first layer containingsilicon, nitrogen and carbon on the wafer 200; and a process in which aprocess of supplying a chlorosilane-based source gas (HCDS gas) to thewafer 200 in the process chamber 201 and a process of supplying anitrogen-containing gas (NH₃ gas) to the wafer 200 in the processchamber 201 are alternately performed a predetermined number of times(m′ times) to form a SiN layer as a second layer on the first layer; maybe performed a predetermined number of times (n times) to form a SiCNfilm having a predetermined composition and a predetermined filmthickness formed by alternately depositing the first layer and thesecond layer on the wafer 200. FIG. 9C shows an example in which a setof steps 1 and 2 and a set of steps 1 and 3 are performed twice percycle, i.e., an example in which a process of performing a set of steps1 and 2 twice and a process of performing a set of steps 1 and 3 twiceare set as one cycle and the cycle is performed a predetermined numberof times (n times). In addition, the variant is distinguished from theabove-mentioned film-forming sequence shown in FIGS. 7 and 8 in that,after a set of steps 1 and 2 is performed a predetermined number oftimes (m times), a set of steps 1 and 3 is performed a predeterminednumber of times (m′ times), and the above is set as one cycle, whileeverything else is similar to the above-mentioned film-forming sequence.In addition, the case in which the number of times m the set of steps 1and 2 is performed is one and the number of times m′ the set of steps 1and 3 is performed is one in the variant corresponds to the film-formingsequence of variant 2 shown in FIG. 9B.

In such a variant, effects similar to the above-mentioned film-formingsequence shown in FIGS. 7 and 8 will be provided. In addition, accordingto such a variant, a ratio of the silicon element, the nitrogen elementand the carbon element in the SiCN film can be more accuratelycontrolled, and controllability of a composition ratio of the SiCN filmcan be improved.

For example, as the number m of sets including step 1 and step 2 isincreased in variant 1, absolute amounts of the silicon element, thenitrogen element and the carbon element of the first layer can beincreased. Accordingly, the first layer in which the absolute values ofthe respective elements are increased is nitride in step 3, a ratio ofthe silicon element and the carbon element with respect to the nitrogenelement of the SiCN layer can be controlled to be increased, and theratio of the silicon element and the carbon element with respect to thenitrogen element of the finally formed SiCN film can be controlled to beincreased.

In addition, for example, as the number m of sets including step 1 andstep 2 is reduced in variant 1, absolute values of the silicon element,the nitrogen element and the carbon element of the first layer can bereduced. Accordingly, the first layer in which the absolute values ofthe respective elements are reduced is nitride in step 3, the ratio ofthe silicon element and the carbon element with respect to the nitrogenelement of the SiCN layer can be controlled to be reduced, and the ratioof the silicon element and the carbon element with respect to thenitrogen element of the finally formed SiCN film can be controlled to bereduced.

Even in variants 2 and 3, the ratio of the silicon element, the nitrogenelement and the carbon element of the SiCN film can be more accuratelycontrolled according to the same principle.

In addition, according to such a variant, a thickness of the layerformed in one cycle can be increased, and a cycle rate (a thickness ofthe SiCN layer formed in unit cycle) can be improved. Accordingly, thefilm-forming rate can also be improved.

For example, in variants 1 and 3, as the number m of sets including step1 and step 2 is increased, the number of layers of the first layerformed in one cycle, i.e., the thickness of the first layer formed inone cycle, can be increased according to the number m of sets, and thecycle rate can be improved. In addition, as the number m′ of setsincluding step 1 and step 3 is increased in variant 3, the number oflayers of the SiN layer as the second layer formed in one cycle, i.e.,the thickness of the second layer formed in one cycle, can be increasedaccording to the set number m′, and thus the cycle rate can also beimproved. In addition, since step 1 is preformed twice by one cycle invariant 2, the cycle rate can be improved even in variant 2.Accordingly, the film-forming rate can also be improved.

In addition, a sequence of a process of forming a first layer containingSi, N and C and a process of forming a SiN layer as a second layer maybe changed. That is, the process of forming the first layer may beperformed after the process of forming the second layer (the SiN layer)is performed, and the above may be set as one cycle. In addition, thevariant may be arbitrarily combined and used.

Third Embodiment of the Invention

Next, a third embodiment of the present invention will be described.

In the above-mentioned first embodiment, while an example in which thesilicon oxycarbonitride film or the silicon oxycarbide film having apredetermined composition and a predetermined film thickness is formedon the wafer 200 using the oxygen-containing gas (O₂ gas) as the secondreactive gas has been described, in the embodiment, an example in whicha silicon oxycarbonitride film having a predetermined composition andpredetermined film thickness is formed on the wafer 200 using anitrogen-containing gas (NH₃ gas) and an oxygen-containing gas (O₂ gas)as a second reactive gas will be described.

That is, in the embodiment, an example in which a cycle including aprocess in which a process of supplying HCDS gas as a source gas, whichis a chlorosilane-based source gas, to the wafer 200 in the processchamber 201 and a process of supplying TEA gas as a first reactive gas,which is an amine-based gas, containing the three elements includingcarbon, nitrogen and hydrogen, having a composition wherein the numberof carbon atoms is greater than that of nitrogen atoms in one molecule,and containing a plurality of (three) ligands (an ethyl group)containing a carbon atom to the wafer 200 in the process chamber 201 arealternately performed once to form a first layer containing silicon,nitrogen and carbon on the wafer 200; and a process of supplying NH₃gas, which is a nitrogen-containing gas (a nitriding gas), and O₂ gas,which is an oxygen-containing gas (an oxidizing gas), as a secondreactive gas different from the source gas and the first reactive gas,to the wafer 200 in the process chamber 201 to modify the first layer toform a silicon oxycarbonitride layer (a SiOCN layer) as a second layer;is performed a predetermined number of times (n times) to form a siliconoxycarbonitride film (a SiOCN film) having a predetermined compositionand a predetermined film thickness on the wafer 200 will be described.

FIG. 10 is a view showing a film-forming flow of the embodiment. FIG. 11is a view showing a gas supply timing in a film-forming sequence of theembodiment. In addition, the embodiment is distinguished from the firstembodiment in that, after steps 1 and 2 are performed to form a firstlayer, step 3 of supplying NH₃ gas, which is a nitrogen-containing gas,as a second reactive gas to nitride the first layer, and step 4 ofsupplying O₂ gas, which is an oxygen-containing gas, as the secondreactive gas to oxidize the first layer after nitridation to be modifiedinto a SiOCN layer as a second layer are performed, steps 1 to 4 are setas one cycle, and the cycle is performed a predetermined number oftimes, while everything else is similar to the first embodiment. Inaddition, a sequence and processing conditions of step 3 of theembodiment or a reaction generated thereby are similar to a sequence andprocessing conditions of step 3 of the second embodiment and a reactiongenerated thereby. Further, a sequence and processing conditions of step4 of the embodiment or a reaction generated thereby are similar to asequence and processing conditions of step 3 of the first embodiment ora reaction generated thereby.

According to the embodiment, after steps 1 and 2 are alternatelyperformed once to form the first layer containing Si, N and C, step 3 ofsupplying NH₃ gas as a second reactive gas, which is anitrogen-containing gas, to nitride the first layer to be modified intoa SiCN layer and step 4 of supplying O₂ gas as a second reactive gas,which is an oxygen-containing gas, to oxidize the first layer (the SiCNlayer) after nitridation to be modified into a SiOCN layer as a secondlayer may be performed to adjust a composition ratio of oxygen, carbonand nitrogen in the formed SiOCN film. Accordingly, permittivity of theformed SiOCN film can be adjusted, an etching resistance can beimproved, or a leak resistance can be improved.

In addition, according to the embodiment, effects similar to theabove-mentioned first and second embodiments are provided. That is, byusing the TEA gas, which is an amine-based gas containing the threeelements including carbon, nitrogen and hydrogen, having a compositionwherein the number of carbon atoms is greater than that of nitrogenatoms, and containing no silicon and no metal, as a first reactive gas,a carbon concentration of the SiOCN film can be increased, reactioncontrollability, in particular, composition controllability, uponformation of the SiOCN film can be improved, an impurity concentrationin the film can be reduced, or film thickness uniformity in a surface ofthe wafer 200 and between surfaces of the wafers 200 can be improved. Inaddition, as the NH₃ gas or the O₂ gas is thermally activated (excited)and supplied as the second reactive gas, a composition ratio of theSiOCN film can be appropriately adjusted.

Variant

In the above-mentioned film-forming sequence shown in FIGS. 10 and 11,while an example in which steps 1 to 4 are set as one cycle and thecycle is performed a predetermined number of times has been described,the film-forming sequence according to the embodiment is not limitedthereto but may be varied as described below.

For example, like variant 1 shown in FIG. 12A, after steps 1 and 2 areset as one set and the set is performed a predetermined number of times(m times), steps 3 and 4 may be sequentially performed, and the abovemay be set as one cycle and the cycle may be performed a predeterminednumber of times (n times). That is, a cycle including a process in whicha process of supplying a chlorosilane-based source gas (HCDS gas) to thewafer 200 in the process chamber 201 and a process of supplying anamine-based gas (TEA gas) containing the three elements includingcarbon, nitrogen and hydrogen and having a composition wherein thenumber of carbon atoms is greater than that of nitrogen atoms to thewafer 200 in the process chamber 201 are alternately performed apredetermined number of times (m times) to form a first layer containingsilicon, nitrogen and carbon on the wafer 200; and a process ofsequentially supplying a nitrogen-containing gas (NH₃ gas) and anoxygen-containing gas (O₂ gas) to the wafer 200 in the process chamber201 to modify the first layer to form a SiOCN layer as a second layer;may be performed a predetermined number of times (n times) to form aSiOCN film having a predetermined composition and a predetermined filmthickness on the wafer 200. FIG. 12A shows an example in which steps 1and 2 are performed twice per cycle, i.e., an example in which a processof performing a set of steps 1 and 2 twice and a process of performingsteps 3 and 4 twice are set as one cycle and the cycle is performed apredetermined number of times (n times). The variant is distinguishedfrom the above-mentioned film-forming sequence shown in FIGS. 10 and 11in that after a set of steps 1 and 2 is performed a predetermined numberof times (m times), steps 3 and 4 are sequentially performed, and theabove is set as one cycle, while everything else is similar to theabove-mentioned film-forming sequence. In addition, the case in whichthe number of times m the set of steps 1 and 2 is performed is one inthe variant corresponds to the above-mentioned film-forming sequenceshown in FIGS. 10 and 11.

In addition, for example, like variant 2 shown in FIG. 12B, after steps1 to 3 are set as one set and the set is performed a predeterminednumber of times (m times), step 4 may be performed, and the above may beset as one cycle and the cycle may be performed a predetermined numberof times (n times). That is, a cycle including a process in which a setincluding a process of supplying a chlorosilane-based source gas (HCDSgas) to the wafer 200 in the process chamber 201, a process of supplyingan amine-based gas (TEA gas) containing the three elements includingcarbon, nitrogen and hydrogen and having a composition wherein thenumber of carbon atoms is greater than that of nitrogen atoms to thewafer 200 in the process chamber 201, and a process of supplying anitrogen-containing gas (NH₃ gas) to the wafer 200 in the processchamber 201 is performed a predetermined number of times (m times) toform a SiCN layer as a first layer on the wafer 200; and a process ofsupplying an oxygen-containing gas (O₂ gas to the wafer 200 in theprocess chamber 201 to modify the first layer to form a SiOCN layer as asecond layer; may be performed a predetermined number of times (n times)to form a SiOCN film having a predetermined composition and apredetermined film thickness on the wafer 200. FIG. 12B shows an examplein which a set of steps 1 to 3 is performed twice per cycle, i.e., anexample in which a process of performing a set of steps 1 to 3 isperformed twice and a process of performing step 4 are set as one cycleand the cycle is performed a predetermined number of times (n times).The variant is distinguished from the above-mentioned film-formingsequence shown in FIGS. 10 and 11 in that, after the set of steps 1 to 3is performed a predetermined number of times (m times), step 4 isperformed, and the above is set as one cycle, while everything else issimilar to the above-mentioned film-forming sequence. In addition, thecase in which the number of times m the set of steps 1 to 3 is performedis one in the variant corresponds to the above-mentioned film-formingsequence shown in FIGS. 10 and 11.

In addition, for example, like variant 3 shown in FIG. 13A, steps 1, 2,3, 1, and 4 may be sequentially performed and set as one cycle, and thecycle may be performed a predetermined number of times (n times). Thatis, a cycle including a process in which a set including a process ofsupplying a chlorosilane-based source gas (HCDS gas) to the wafer 200 inthe process chamber 201, a process of supplying an amine-based gas (TEAgas) containing the three elements including carbon, nitrogen andhydrogen and having a composition wherein the number of carbon atoms isgreater than that of nitrogen atoms to the wafer 200 in the processchamber 201, and a process of supplying a nitrogen-containing gas (NH₃gas) to the wafer 200 in the process chamber 201 is performed once toform a SiCN layer as a first layer on the wafer 200; and a process inwhich a set including a process of supplying a chlorosilane-based sourcegas (HCDS gas) to the wafer 200 in the process chamber 201 and a processof supplying an oxygen-containing gas (O₂ gas) to the wafer 200 in theprocess chamber 201 is performed once to form a silicon oxide layer (aSiO layer) as a second layer on the first layer; may be performed apredetermined number of times (n times) to form a SiOCN film having apredetermined composition and a predetermined film thickness formed byalternately depositing the first layer and the second layer on the wafer200. In addition, the variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 10 and 11 in that steps 1, 2, 3, 1,and 4 are set as one cycle, and everything else is similar to theabove-mentioned film-forming sequence.

In addition, for example, like variant 4 shown in FIG. 13B, after steps1 to 3 are set as one set and the set is performed a predeterminednumber of times (m times), steps 1 and 4 may be set as one set and theset may be performed a predetermined number of times (m′ times), and thecombinations may be set as one cycle and the cycle may be performed apredetermined number of times (n times). That is, a cycle including aprocess in which a set including a process of supplying achlorosilane-based source gas (HCDS gas) to the wafer 200 in the processchamber 201, a process of supplying an amine-based gas (TEA gas)containing the three elements including carbon, nitrogen and hydrogenand having a composition wherein the number of carbon atoms is greaterthan that of nitrogen atoms to the wafer 200 in the process chamber 201,and a process of supplying a nitrogen-containing gas (NH₃ gas) to thewafer 200 in the process chamber 201 is performed a predetermined numberof times (m times) to form a SiCN layer as a first layer on the wafer200; and a process in which a set including a process of supplying achlorosilane-based source gas (HCDS gas) to the wafer 200 in the processchamber 201 and a process of supplying an oxygen-containing gas (O₂ gas)to the wafer 200 in the process chamber 201 is performed a predeterminednumber of times (m′ times) to form a SiO layer as a second layer on thefirst layer; may be performed a predetermined number of times (n times)to form a SiOCN film having a predetermined composition and apredetermined film thickness formed by alternately depositing the firstlayer and the second layer on the wafer 200. FIG. 13B shows an examplein which a set of steps 1 to 3 and a set of steps 1 and 4 arerespectively performed twice per cycle, i.e., an example in which aprocess of performing a set of steps 1 to 3 twice and a process ofperforming a set of steps 1 and 4 twice are set as one cycle and thecycle is performed a predetermined number of times (n times). Inaddition, the variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 10 and 11 in that, after a set ofsteps 1 to 3 is performed a predetermined number of times (m times), aset of steps 1 and 4 is performed a predetermined number of times (m′times), and the above is set as one cycle, while everything else issimilar to the above-mentioned film-forming sequence. In addition, thecase in which the number of times m the set of steps 1 to 3 areperformed is one and the performing number m′ of the set of steps 1 and4 in the variant is one corresponds to the film-forming sequence ofvariant 3 shown in FIG. 13A.

In addition, for example, like variant 5 shown in FIG. 14A, steps 1, 2,1, 3, and 4 may be sequentially performed and set as one cycle and thecycle may be performed a predetermined number of times. That is, a cycleincluding a process in which a set including a process of supplying achlorosilane-based source gas (HCDS gas) to the wafer 200 in the processchamber 201 and a process of supplying an amine-based gas (TEA gas)containing the three elements including carbon, nitrogen and hydrogenand having a composition wherein the number of carbon atoms is greaterthan that of nitrogen atoms to the wafer 200 in the process chamber 201is performed once to form a first layer containing silicon, nitrogen andcarbon on the wafer 200; a process in which a set including a process ofsupplying a chlorosilane-based source gas (HCDS gas) to the wafer 200 inthe process chamber 201, a process of supplying a nitrogen-containinggas (NH₃ gas) to the wafer 200 in the process chamber 201, and a processof supplying an oxygen-containing gas (O₂ gas) to the wafer 200 in theprocess chamber 201 is performed once to form a silicon oxynitride layer(a SiON layer) as a second layer on the first layer; may be performed apredetermined number of times (n times) to form a SiOCN film having apredetermined composition and a predetermined film thickness formed byalternately depositing the first layer and the second layer on the wafer200. In addition, the variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 10 and 11 in that steps 1, 2, 1, 3,and 4 are set at one cycle, and everything else is similar to theabove-mentioned film-forming sequence.

In addition, for example, like variant 6 shown in FIG. 14B, after steps1 and 2 are set as one set and the set is performed a predeterminednumber of times (m times), steps 1, 3 and 4 may be set as one set andthe set may be performed a predetermined number of times (m′ times), andthe above may be set as one cycle and the cycle may be performed apredetermined number of times (n times). That is, a cycle including aprocess in which a set including a process of supplying achlorosilane-based source gas (HCDS gas) to the wafer 200 in the processchamber 201 and a process of supplying an amine-based gas (TEA gas)containing the three elements including carbon, nitrogen and hydrogenand having a composition wherein the number of carbon atoms is greaterthan that of nitrogen atoms to the wafer 200 in the process chamber 201is performed a predetermined number of times (m times) to form a firstlayer containing silicon (Si), nitrogen (N) and carbon (C) on the wafer200; a process in which a set including a process of supplying achlorosilane-based source gas (HCDS gas) to the wafer 200 in the processchamber 201, a process of supplying a nitrogen-containing gas (NH₃ gas)to the wafer 200 in the process chamber 201, and a process of supplyingan oxygen-containing gas (O₂ gas) to the wafer 200 in the processchamber 201 is performed a predetermined number of times (m′ times) toform a SiON layer as a second layer on the first layer; may be performeda predetermined number of times (n times) to form a SiOCN film having apredetermined composition and a predetermined film thickness formed byalternately depositing the first layer and the second layer on the wafer200. FIG. 14B shows an example in which a set of steps 1 and 2 and a setof steps 1, 3 and 4 are respectively performed twice per cycle, i.e., anexample in which a process of performing a set of steps 1 and 2 twiceand a process of performing a set of steps 1, 3 and 4 twice are set asone cycle and the cycle is performed a predetermined number of times (ntimes). The variant is distinguished from the above-mentionedfilm-forming sequence shown in FIGS. 10 and 11 in that after a set ofsteps 1 and 2 is performed a predetermined number of times (m times), aset of steps 1, 3 and 4 is performed a predetermined number of times (m′times), and the above is set as one cycle, while everything else issimilar to the above-mentioned film-forming sequence. In addition, thecase in which the number of times m the set of steps 1 and 2 isperformed is one and the number of times m′ the set of steps 1, 3 and 4is performed is one in the variant corresponds to the film-formingsequence of the variant 5 shown in FIG. 14A.

Even in the variant, effects similar to the above-mentioned film-formingsequence shown in FIGS. 10 and 11 can be provided. In addition,according to such a variant, a ratio of the silicon element, thenitrogen element, the carbon element and the oxygen element in the SiOCNfilm can be more accurately controlled, and controllability of thecomposition ratio of the SiOCN film can be improved. In addition,according to the variant, a thickness of the layer formed by one cyclecan be increased, and a cycle rate (a thickness of the SiOCN layerformed by a unit cycle) can be improved. Accordingly, a film-formingrate can also be improved.

In addition, in the variants 3 and 4, the process of forming the SiCNlayer as the first layer and the process of forming the SiO layer as thesecond layer may be changed. That is, the process of forming the SiCNlater may be performed after the process of forming the SiO layer isperformed, and the above may be set as one cycle. In addition, invariants 5 and 6, the process of forming the first layer containing Si,N and C and the process of forming the SiON layer as the second layermay be changed. That is, after the process of forming the SiON layer isperformed, the process of forming the first layer is performed, and theabove may be set as one cycle. In addition, the variant may bearbitrarily combined and used.

Another Embodiment of the Invention

Hereinabove, while the embodiment of the present invention has beenspecifically described, the present invention is not limited to theabove-mentioned embodiment but may be varied without departing from thespirit of the present invention.

For example, in the above-mentioned embodiment, while the example inwhich the chlorosilane-based source gas is supplied to the wafer 200 inthe process chamber 201 when the first layer containing Si, N and C isformed, and then the amine-based gas is supplied has been described, thesupply sequence of the gases may be reversed. That is, the amine-basedgas may be supplied, and then the chlorosilane-based source gas may besupplied. That is, one of the chlorosilane-based source gas and theamine-based gas may be supplied, and then the other gas may be supplied.As described above, as the supply sequence of the gases is varied, filmquality or a composition ratio of the formed thin film can be varied.

In addition, for example, in the above-mentioned embodiment, while anexample in which the chlorosilane-based source gas is used as the sourcegas when the initial layer containing the predetermined element(silicon) and the halogen element (chlorine) is formed in step 1 hasbeen described, the silane-based source gas having a halogen-basedligand other than the chloro group may be used instead of thechlorosilane-based source gas. For example, a fluorosilane-based sourcegas may be used instead of the chlorosilane-based source gas. Here, thefluorosilane-based source gas refers to a fluorosilane-based sourcematerial in a gaseous state, for example, a gas obtained by vaporizing afluorosilane-based source material in a liquid state under a normaltemperature and a normal pressure, or a fluorosilane-based sourcematerial in a gaseous state under a normal temperature and a normalpressure. In addition, the fluorosilane-based source material is asilane-based source material containing a fluoro group, which is ahalogen group, and is a source material containing at least silicon (Si)and fluorine (F). That is, the fluorosilane-based source materialdisclosed herein may be referred to as a kind of halide. For example,silicon fluoride gas such as tetrafluorosilane, i.e., silicontetrafluoride (SiF₄) gas, or hexafluorodisilane (Si₂F₆) gas, may be usedas the fluorosilane-based source gas. In this case, when an initiallayer containing a predetermined element and a halogen element isformed, the fluorosilane-based source gas is supplied to the wafer 200in the process chamber 201. In this case, the initial layer becomes alayer containing Si and F, i.e., a silicon-containing layer containingF.

In addition, for example, in the above-mentioned embodiment, while anexample in which the amine-based gas is used as the first reactive gaswhen the silicon-containing layer containing Cl as the initial layer ismodified into the first layer containing Si, N and C has been described,a gas containing, for example, an organic hydrazine compound, i.e., anorganic hydrazine-based gas, may be used as the first reactive gasinstead of the amine-based gas. In addition, the gas containing anorganic hydrazine compound may be simply referred to as an organichydrazine compound gas or an organic hydrazine gas. Here, the organichydrazine-based gas is organic hydrazine in a gaseous state, forexample, a gas obtained by vaporizing organic hydrazine in a liquidstate under a normal temperature and a normal pressure, or a gascontaining a hydrazine group such as organic hydrazine in a gaseousstate under a normal temperature and a normal pressure. The organichydrazine-based gas is a gas containing the three elements includingcarbon (C), nitrogen (N) and hydrogen (H) and containing no silicon, ora gas containing no silicon and no metal. For example, a methylhydrazine-based gas formed by vaporizing monomethyl hydrazine[(CH₃)HN₂H₂, abbreviation: MMH], dimethyl hydrazine [(CH₃)₂N₂H₂,abbreviation: DMH], or trimethyl hydrazine [(CH₃)₂N₂(CH₃)H,abbreviation: TMH], or an ethyl hydrazine-based gas formed by vaporizingethyl hydrazine [(C₂H₅)HN₂H₂, abbreviation: EH] may be used as theorganic hydrazine-based gas. In this case, when the silicon-containinglayer containing Cl as the initial layer is modified into the firstlayer containing Si, N and C, the organic hydrazine-based gas issupplied to the wafer 200 in the process chamber 201. In addition, a gascontaining the three elements including carbon, nitrogen and hydrogenand having a composition wherein the number of carbon atoms is greaterthan that of nitrogen atoms in one molecule may be used as the organichydrazine-based gas. In addition, a gas containing a plurality ofligands containing a carbon (C) atom in one molecule, i.e., a gascontaining a plurality of hydrocarbon groups such as an alkyl group inone molecule, may be used as the organic hydrazine-based gas.Specifically, a gas containing three or two ligands (hydrocarbon groupssuch as alkyl groups) containing a carbon (C) atom in one molecule maybe used as the organic hydrazine-based gas.

In addition, for example, in the above-mentioned embodiment, while anexample in which the chlorosilane-based source gas is supplied to thewafer 200 in the process chamber 201 when the first layer containing Si,N and C is formed, and then the amine-based gas is supplied has beendescribed, as shown in FIG. 15A, the chlorosilane-based source gas andthe amine-based gas may be simultaneously supplied to the wafer 200 inthe process chamber 201 to generate a CVD reaction.

A sequence of FIGS. 15A and 15B is an example in which a cycle includinga process of simultaneously supplying a chlorosilane-based source gas(HCDS gas), and an amine-based gas (TEA gas) containing the threeelements including carbon, nitrogen and hydrogen and having acomposition wherein the number of carbon atoms is greater than that ofnitrogen atoms to the wafer 200 in the process chamber 201 to form afirst layer containing silicon, nitrogen and carbon on the wafer 200;and a process of supplying an oxygen-containing gas (O₂ gas), which is asecond reactive gas, to the wafer 200 in the process chamber 201 tomodify the first layer to form a SiOCN layer or a SiOC layer as a secondlayer; is performed a predetermined number of times (n times) to form aSiOCN film or a SiOC film having a predetermined composition and apredetermined film thickness on the wafer 200. In addition, FIG. 15Ashows the case in which a process of simultaneously supplying HCDS gasand TEA gas is performed once in one cycle, and FIG. 15B shows the casein which a process of simultaneously supplying HCDS gas and TEA gas isperformed a plurality of times (twice) by one cycle. In addition, theprocessing conditions in this case may also be processing conditionssimilar to the processing conditions in the above-mentioned embodiment.

As described, even when the chlorosilane-based source gas and theamine-based gas are simultaneously, rather than sequentially, suppliedto the wafer 200 in the process chamber 201, effects similar to theabove-mentioned embodiment can be obtained. However, alternate supply ofthe chlorosilane-based source gas and the amine-based gas with the purgein the process chamber 201 interposed therebetween like in theabove-mentioned embodiment can appropriately cause reaction of thechlorosilane-based source gas with the amine-based gas under a conditionthat a surface reaction is dominant, and controllability of filmthickness can be improved.

As the silicon insulating film formed by techniques of theabove-mentioned embodiments or variants is used as a sidewall spacer, adevice forming technique having a small leak current and goodmachinability can be provided.

As the silicon insulating film formed by a technique of theabove-mentioned embodiments or variants is used as an etching stopper, adevice forming technique having good machinability can be provided.

According to the above-mentioned embodiments or variants, the siliconinsulating film having an ideal stoichiometric mixture ratio can beformed without using plasma even at a low temperature region. Inaddition, since the silicon insulating film can be formed with no use ofplasma, for example, application to a process having probability ofplasma damage, for example, an SADP film of DPT, is also possible.

In addition, in the above-mentioned embodiment, while an example inwhich the silicon-based insulating film (the SiOCN film, the SiOC film,or the SiCN film) containing silicon, which is a semiconductor element,is formed as an oxycarbonitride film, an oxycarbide film, or acarbonitride film has been described, the present invention may beapplied to the case in which a metal-based thin film containing a metalelement such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum(Ta), aluminum (Al), molybdenum (Mo), or the like is used.

That is, the present invention may be applied to the case in which ametal oxycarbonitride film such as a titanium oxycarbonitride film (aTiOCN film), a zirconium oxycarbonitride film (a ZrOCN film), a hafniumoxycarbonitride film (a HfOCN film), a tantalum oxycarbonitride film (aTaOCN film), an aluminum oxycarbonitride film (an AlOCN film), amolybdenum oxycarbonitride film (a MoOCN film), or the like, is formed.

In addition, for example, the present invention may be applied to thecase in which a metal oxycarbide film such as a titanium oxycarbide film(a TiOC film), a zirconium oxycarbide film (a ZrOC film), a hafniumoxycarbide film (a HfOC film), a tantalum oxycarbide film (a TaOC film),an aluminum oxycarbide film (an AlOC film), a molybdenumoxycarbide film(a MoOC film), or the like, is formed.

Further, for example, the present invention may also be applied to thecase in which a metal carbonitride film such as a titanium carbonitridefilm (a TiCN film), a zirconium carbonitride film (a ZrCN film), ahafnium carbonitride film (a HfCN film), a tantalum carbonitride film (aTaCN film), an aluminum carbonitride film (an AlCN film), a molybdenumcarbonitride film (a MoCN film), or the like, is formed.

In this case, film-forming may be performed by a sequence similar to theabove-mentioned embodiment using a source gas containing a metal elementand a halogen element, instead of the chlorosilane-based source gas inthe above-mentioned embodiment. That is, a cycle including a process inwhich a process of supplying a source gas containing a metal element anda halogen element to the wafer 200 in the process chamber 201 and aprocess of supplying a first reactive gas containing the three elementsincluding carbon, nitrogen and hydrogen and having a composition whereinthe number of carbon atoms is greater than that of nitrogen atoms to thewafer 200 in the process chamber 201 are alternately performed apredetermined number of times to form a first layer containing a metalelement, nitrogen and carbon on the wafer 200; and a process ofsupplying a second reactive gas different from the source gas and thefirst reactive gas to the wafer 200 in the process chamber 201 to modifythe first layer to form a second layer; may be performed a predeterminednumber of times to form a metal-based thin film (a metal oxycarbonitridefilm, a metal oxycarbide film, or a metal carbonitride film) having apredetermined composition and a predetermined film thickness on thewafer 200.

For example, when a metal-based thin film (a TiOCN film, a TiOC film, ora TiCN film) containing Ti is formed, a gas containing Ti and a chlorogroup such as titanium tetrachloride (TiCl₄) or a gas containing Ti anda fluoro group such as titanium tetrafluoride (TiF₄) may be used as thesource gas. A gas similar to the above-mentioned embodiment may be usedas the first and second reactive gases. In addition, the processingconditions at this time may be, for example, processing conditionssimilar to the above-mentioned embodiment.

In addition, for example, when a metal-based thin film containing Zr (aZrOCN film, a ZrOC film, or a ZrCN film) is formed, a gas containing Zrand a chloro group such as zirconium tetrachloride (ZrCl₄) or a gascontaining Zr and a fluoro group such as zirconium tetrafluoride (ZrF₄)may be used as the source gas. The same gas as of the above-mentionedembodiment may be used as the first and second reactive gases. Further,the processing conditions at this time may be substantially the sameprocessing conditions as of the above-mentioned embodiment.

In addition, for example, when a metal-based thin film containing Hf (aHfOCN film, a HfOC film, or a HfCN film) is formed, a gas containing Hfand a chloro group such as hafnium tetrachloride (HfCl₄) or a gascontaining Hf and a fluoro group such as hafnium tetrafluoride (HfF₄)may be used as the source gas. The same gas as of the above-mentionedembodiment may be used as the first and second reactive gases. Further,the processing conditions at this time may be substantially the sameprocessing conditions as of the above-mentioned embodiment.

In addition, for example, when a metal-based thin film containing Ta (aTaOCN film, a TaOC film, or a TaCN film) is formed, a gas containing Taand a chloro group such as tantalum pentachloride (TaCl₅) or a gascontaining Ta and a fluoro group such as tantalum pentafluoride (TaF₅)may be used as the source gas. The same gas as of the above-mentionedembodiment may be used as the first and second reactive gases. Further,the processing conditions at this time may be substantially the sameprocessing conditions as of the above-mentioned embodiment.

In addition, for example, when a metal-based thin film containing Al (anAlOCN film, an AlOC film, or an AlCN film) is formed, a gas containingAl and a chloro group such as aluminum trichloride (AlCl₃) or a gascontaining Al and a fluoro group such aluminum trifluoride (AlF₃) may beused as the source gas. The same gas as of the above-mentionedembodiment may be used as the first and second reactive gases. Further,the processing conditions at this time may be substantially the sameprocessing conditions as of the above-mentioned embodiment.

In addition, for example, when a metal-based thin film containing Mo (aMoOCN film, a MoOC film, or a MoCN film) is formed, a gas containing Moand a chloro group such as molybdenum pentachloride (MoCl₅) or a gascontaining Mo and a fluoro group such as molybdenum pentafluoride (MoF₅)may be used as the source gas. The same gas as of the above-mentionedembodiment may be used as the first and second reactive gases. Further,the processing conditions at this time may be substantially the sameprocessing conditions as of the above-mentioned embodiment.

That is, the present invention may be applied to the case in which athin film containing a predetermined element such as a semiconductorelement or a metal element is formed.

In addition, in the above-mentioned embodiment, while an example inwhich the thin film is formed using a batch type substrate processingapparatus in which a plurality of substrates are processed at a time hasbeen described, the present invention is not limited thereto but may beapplied to the case in which the thin film is formed using a sheet-feedtype substrate processing apparatus in which one or several substratesare processed at a time. In addition, in the above-mentioned embodiment,while an example in which the thin film is formed using the substrateprocessing apparatus including a hot wall type processing furnace hasbeen described, the present invention is not limited thereto but may beapplied to the case in which the thin film is formed using the substrateprocessing apparatus including a cold wall type processing furnace.

In addition, the above-mentioned embodiments, variants, and applicationexamples may be appropriately combined and used.

Further, the present invention is realized by varying, for example, aprocess recipe of the substrate processing apparatus in the related art.When the process recipe is varied, the process recipe according to thepresent invention may be installed at the substrate processing apparatusin the related art via a electrical communication line or anon-transitory computer readable recording medium in which the processrecipe is recorded, or the process recipe itself may be changed into theprocess recipe according to the present invention by manipulating aninput/output device of the substrate processing apparatus in the relatedart.

Example 1

SiOCN films were formed on a plurality of wafers by the film-formingsequence of the above-mentioned first embodiment using the substrateprocessing apparatus of the above-mentioned embodiment. HCDS gas wasused as a source gas, TEA gas was used as a first reactive gas, and O₂gas was used as a second reactive gas. A wafer temperature uponfilm-forming was 600 to 650° C. Here, a supply time of the O₂ gas instep 3 was varied to 0 seconds, 3 seconds and 6 seconds, and threeestimation samples were drafted. The other processing conditions wereset as predetermined values within a range of the processing conditionsdescribed in the above-mentioned first embodiment. Hereinafter, theestimation samples drafted by setting the supply times of the O₂ gas instep 3 to 0 seconds, 3 seconds and 6 seconds are referred to asestimation samples A, B and C, respectively. In addition, the supplytime of the O₂ gas=0 seconds refers to the case in which the O₂ gas isnot supplied, i.e., the case in which a material containing Si, N and C(hereinafter, simply referred to as “a SiCN film”) is formed by asequence in which step 1 and step 2 of the film-forming sequence of theabove-mentioned first embodiment are alternately repeated (a referenceexample). Then, film thickness uniformity in a wafer surface(hereinafter referred to as WIW), film thickness uniformity betweensurfaces of the wafers (hereinafter referred to as WTW), a refractiveindex (hereinafter referred to as R.I.), an XPS composition ratio, and awet etching rate (hereinafter referred to as WER) with respect to aliquid containing hydrogen fluoride (HF) having a concentration of 1.0%of each estimation sample were measured. The measurement results areshown in FIG. 16.

As shown in FIG. 16, it was confirmed that the film thickness uniformity(WIW) in the wafer surface and the film thickness uniformity (WTW)between the surfaces of the wafers of the SiCN film of the estimationsample A formed as the reference example become 2.7% and 2.5%,respectively. In addition, it was confirmed that the film thicknessuniformity (WIW) in the wafer surface and the film thickness uniformity(WTW) between the surfaces of the wafers of the SiOCN film of theestimation sample B formed in the example become 2.9% and 2.2%,respectively. Further, it was confirmed that the film thicknessuniformity (WIW) in the wafer surface and the film thickness uniformity(WTW) between the surfaces of the wafers of the SiOCN film of theestimation sample C formed in the example become 2.1% and 2.4%,respectively. Furthermore, both of WIW and WTW represent that the filmthickness uniformity is increased, i.e., that the film thicknessuniformity becomes better, as the value thereof is reduced. That is, itwas confirmed that both of the film thickness uniformity in the wafersurface and the film thickness uniformity between the surfaces of thewafers of the SiCN film of the estimation sample A formed in thereference example and the SiOCN films of the estimation samples B and Cformed in the example are good.

In addition, it was confirmed that R.I. of the film of the estimationsample A formed as the reference example is 2.2, and the formed film isthe SiCN film. Further, it was confirmed that R.I. of the film of theestimation sample B formed in the example is 1.8, and the formed film isthe SiOCN film. Furthermore, it was confirmed that R.I. of the film ofthe estimation sample C formed in the example is 1.6, and the formedfilm is the SiOCN film. As a result, it was confirmed that R.I. isreduced as the supply time of the O₂ gas in step 3 is increased. Thatis, it was confirmed that R.I. can be controlled by controllingconditions such as the supply time of the O₂ gas in step 3.

In addition, it was confirmed from the XPS measurement result of theSiCN film of the estimation sample A formed as the reference examplethat a ratio of Si/C/N/O in the SiCN film of the estimation sample Aformed in the reference example becomes 40/42/15/3. That is, it wasconfirmed that the SiCN film having a C concentration of 42 at % can beformed. Further, it was confirmed that the Si concentration in the SiCNfilm is 40 at %, the N concentration is 15 at %, and the O concentrationis 3 at %. In addition, while the detected O element is an impuritylevel, this may be caused by a native oxide film formed on an interfacebetween the SiCN film and a bottom surface, or on the SiCN film surface.

In addition, it was confirmed from the XPS measurement result of theSiOCN film of the estimation sample B formed in the example that a ratioof Si/C/N/O in the SiOCN film of the estimation sample B formed in theexample becomes 36/20/12/32. That is, it was confirmed that the SiOCNfilm having a C concentration of 20 at % can be formed. Further, it wasconfirmed that the Si concentration in the SiOCN film is 36 at %, the Nconcentration is 12 at %, and the O concentration is 32 at %.

In addition, it was confirmed from the XPS measurement result of theSiOCN film of the estimation sample C formed in the example that a ratioof Si/C/N/O in the SiOCN film of the estimation sample C formed in theexample becomes 36/9/9/46. That is, it was confirmed that the SiOCN filmhaving a C concentration of 9 at % can be formed. Further, it wasconfirmed that the Si concentration in the SiOCN film is 36 at %, the Nconcentration is 9 at %, and the O concentration is 46 at %.

As a result, it will be appreciated that, as the supply time of the O₂gas in step 3 is increased, the oxidation is performed to increase the Oconcentration of the SiOCN film and reduce the C concentration and the Nconcentration. In the other experiments performed by the inventor(s), itwas confirmed that the N element reaches an impurity level when thesupply time of the O₂ gas is somewhat lengthened and the oxidation isperformed to some extent, and the oxidation is further performed as thesupply time of the O₂ gas is further lengthened so that the N elementbecomes substantially extinct to form the SiOC film.

That is, it was confirmed that the O concentration, the C concentrationor the N concentration of the SiOCN film can be controlled bycontrolling conditions such as the supply time of the O₂ gas in step 3,i.e., the composition ratio of the SiOCN film can be controlled. Inaddition, it was confirmed that the N element can be reduce to animpurity level or become substantially extinct, and the SiOC film canalso be formed.

In addition, it was confirmed that WER of the SiCN film of theestimation sample A formed as the reference example becomes 0.5 Å/min.That is, it was confirmed that the SiCN film having a high etchingresistance can be formed. In addition, it was confirmed that WER of theSiOCN film of the estimation sample B formed in the example becomes 2.5Å/min. That is, it was confirmed that the SiOCN film having a highetching resistance can be formed. In addition, it was confirmed that WERof the SiOCN film of the estimation sample C formed in the examplebecomes 12.9 Å/min. That is, it was confirmed that the SiOCN film havinga high etching resistance can be formed. As a result, it was confirmedthat WER is increased as the supply time of the O₂ gas in step 3 isincreased. That is, it was confirmed that WER can be controlled bycontrolling conditions such as the supply time of the O₂ gas in step 3.

Example 2

SiOC films were formed on a plurality of wafers by the film-formingsequence of the above-mentioned first embodiment using the substrateprocessing apparatus in the above-mentioned embodiment. HCDS gas wasused as a source gas, TEA gas was used as a first reactive gas, and O₂gas was used as a second reactive gas. A wafer temperature uponfilm-forming was 600 to 650° C. Here, the supply time of the O₂ gas instep 3 was set to 20 to 25 seconds to draft an estimation sample. Inaddition, the processing conditions were set to predetermined valueswithin a range of the processing conditions described in theabove-mentioned first embodiment. Hereinafter, the estimation sampledrafted in the example is referred to as an estimation sample D. Then,film thickness uniformity (WIW) in a wafer surface, film thicknessuniformity (WTW) between surfaces of the wafers, a cycle rate, an XRFcomposition ratio and a refractive index (R.I.) in the estimation sampleD were measured. The measurement results are shown in FIG. 17.

As shown in FIG. 17, it was confirmed that film thickness uniformity(WIW) of the wafer surface and film thickness uniformity (WTW) betweensurfaces of the wafers of the SiOC film of the estimation sample Dformed in the example become 1.8% and 0.8%, respectively. That is, itwas confirmed that both of the film thickness uniformity of the wafersurface and the film thickness uniformity between the surfaces of thewafers in the SiOC film of the estimation sample D formed in the exampleare good.

In addition, it was confirmed that a cycle rate of the SiOC film of theestimation sample D formed in the example becomes 0.55 Å/cycle. That is,it was confirmed that the cycle rate having a good practical level,i.e., the film-forming rate, can be realized by the example.

Further, it was confirmed from the XRF measurement result of the SiOCfilm of the estimation sample D formed in the example that a ratio ofSi/O/C/N in the SiOC film of the estimation sample D formed in theexample becomes 56.7/33.5/8.0/1.8. That is, it was confirmed that theSiOC film having a C concentration of 8.0 at % can be formed. Inaddition, it was confirmed that the Si concentration in the SiOC film is56.7 at %, the O concentration is 33.5 at %, and the N concentration is1.8 at %. While the detected N element is an impurity level, it isconsidered that the oxidation is performed as the supply time of the O₂gas in step 3 is increased, and most of N is eliminated from the filmduring the process so that the N element in the film becomes theimpurity level. Further, similar to the above-mentioned description, theoxidation can be further performed by further increasing the supply timeof the O₂ gas, and the N element can become substantially extinct.

In addition, it was confirmed that R.I. of the estimation sample Dformed in the example is 1.57, and the formed film is the SiOC film.

Example 3

SiOCN films were formed on a plurality of wafers by the film-formingsequence of the above-mentioned first embodiment using the substrateprocessing apparatus of the above-mentioned embodiment. HCDS gas wasused as a source gas, TEA gas or DEA gas was used as a first reactivegas, and O₂ gas was used as a second reactive gas. A wafer temperatureupon film-forming was set to 600 to 650° C. Here, two estimation samplesin the case of using the TEA gas and the case using the DEA gas as thefirst reactive gas in step 2 were drafted. In addition, the otherprocessing conditions were set to predetermined values within a range ofthe processing conditions described in the above-mentioned firstembodiment. In addition, the processing conditions when the twoestimation samples are drafted are the same. Hereinafter, the estimationsample drafted using the TEA gas as the first reactive gas is referredto as an estimation sample E, and the estimation sample drafted usingthe DEA gas as the first reactive gas is referred to as an estimationsample F. Then, film thickness uniformity (WIW) in wafer surfaces, filmthickness uniformity (WTW) between surfaces of the wafers, a cycle rate,XRF measurement results, a wet etching rate (WER) with respect to aliquid containing hydrogen fluoride (HF) having a concentration of 1.0%,and a refractive index (R.I.) in the SiOCN films of the estimationsamples E and F were measured. The measurement results are shown in FIG.18.

As shown in FIG. 18, it was confirmed that the film thickness uniformity(WIW) in the wafer surface and the film thickness uniformity (WTW)between surfaces of the wafers of the SiOCN film of the estimationsample E formed in the example become 2.0% and 1.1%, respectively. Inaddition, it was confirmed that the film thickness uniformity (WIW) inthe wafer surface and the film thickness uniformity (WTW) betweensurfaces of the wafers of the SiOCN film of the estimation sample Fformed in the example become 2.0% and 1.3%, respectively. That is, itwas confirmed that both of the film thickness uniformity in the wafersurfaces and the film thickness uniformity between surfaces of thewafers of the SiOCN films of the estimation samples E and F formed inthe example are good, and there is no difference between the samples.

In addition, it was confirmed that a cycle rate of the SiOCN film of theestimation sample E formed in the example becomes 0.55 Å/cycle. Further,it was confirmed that a cycle rate of the SiOCN film of the estimationsample F formed in the example becomes 0.87 Å/cycle. That is, it wasconfirmed that the cycle rates of the SiOCN films of the estimationsamples E and F formed in the example become cycle rates of a practicallevel, and the film-forming rate of the practical level can be realizedby the example.

Further, when cycle rates of the SiOCN films of the estimation samples Eand F formed in the example were compared, it was confirmed that thecycle rate of the SiOCN film of the estimation sample F drafted usingthe DEA gas as the first reactive gas is greater than the cycle rate ofthe SiOCN film of the estimation sample E drafted using the TEA gas asthe first reactive gas. That is, it will be appreciated that the caseusing the DEA gas as the first reactive gas is better than the caseusing the TEA gas as the first reactive gas in a viewpoint of the cyclerate, i.e., the film-forming rate.

In addition, it was confirmed from the XRF measurement result of theSiOCN film of the estimation sample E formed in the example that a ratioof Si/O/C/N in the SiOCN film formed in the example becomes55.1/31.6/10.2/3.1. That is, it was confirmed that the SiOCN film havinga C concentration of 10.2 at % can be formed. In addition, it wasconfirmed that the Si concentration in the SiOCN film is 55.1 at %, theO concentration is 31.6 at %, and the N concentration is 3.1 at %.

Further, it was confirmed from the XRF measurement results of the SiOCNfilm of the estimation sample F formed in the example that a ratio ofSi/O/C/N in the SiOCN film formed in the example becomes56.1/32.7/6.1/5.1. That is, it was confirmed that the SiOCN film havinga C concentration of 6.1 at % can be formed. In addition, it wasconfirmed that the Si concentration of the SiOCN film is 56.1 at %, theO concentration is 32.7 at %, and the N concentration is 5.1 at %.

In addition, it was confirmed that, when ratios of the N concentrationswith respect to the C concentrations (ratios of the N concentrations/theC concentrations) of the SiOCN films of the estimation samples E and Fformed in the example are compared, the ratio of the N concentration/theC concentration (=0.84) of the SiOCN film of the estimation sample Fdrafted using the DEA gas as the first reactive gas is higher than theratio of the N concentration/the C concentration (=0.3) of the SiOCNfilm of the estimation sample E drafted using the TEA gas as the firstreactive gas. That is, it will be appreciated that, when the SiOCN filmis formed under the same processing conditions, the SiOCN film having ahigher ratio of the N concentration/the C concentration can be obtainedin the case of using the DEA gas as the first reactive gas than the caseof using the TEA gas as the first reactive gas. In other words, it willbe appreciated that, when the SiOCN film is formed under the sameprocessing conditions, the SiOCN film having a lower C concentration anda higher N concentration can be formed in the case of using the DEA gasas the first reactive gas than the case of using the TEA gas as thefirst reactive gas. On the other hand, it will be appreciated that, whenthe SiOCN film is formed under the same conditions, the SiOCN filmhaving a higher ratio of the C concentration with respect to the Nconcentration (a ratio of the C concentration/the N concentration) canbe formed in the case of using the TEA gas as the first reactive gasthan the case of using the DEA gas as the first reactive gas. In otherwords, it will be appreciated that, when the SiOCN film is formed underthe same processing conditions, the SiOCN film having a lower Nconcentration and a higher C concentration can be formed in the case ofusing the TEA gas as the first reactive gas than the case of using theDEA gas as the first reactive gas.

In addition, it was confirmed that WER of the SiOCN film of theestimation sample E formed in the example becomes 5.2 Å/min. That is, itwas confirmed that the SiOCN film having a high etching resistance canbe formed. Further, it was confirmed that WER of the SiOCN film of theestimation sample F formed in the example becomes 5.1 Å/min. That is, itwas confirmed that the SiOCN film having a higher etching resistance canbe formed. That is, it was confirmed that the etching resistances of theSiOCN films of the estimation samples E and F formed in the example aregood, and there is no difference between the samples.

In addition, it was confirmed that R.I. of the SiOCN film of theestimation sample E formed in the example is 1.59, and the formed filmis the SiOCN film. Further, it was confirmed that R.I. of the SiOCN filmof the estimation sample F formed in the example is 1.59, and the formedfilm is the SiOCN film. That is, it was confirmed that R.I. values ofthe SiOCN films of the estimation samples E and F formed in the exampleare appropriate values, and there is no difference between the samples.

According to the present invention, there is provided a method ofmanufacturing a semiconductor device in which a thin film havingcharacteristics of low permittivity, high etching resistance and highleak resistance can be formed, a method of processing a substrate, asubstrate processing apparatus and a non-transitory computer readablerecording medium.

Exemplary Aspects of the Invention

Hereinafter, exemplary aspects of the present invention will besupplementarily noted.

Supplementary Note 1

According to an aspect of the present invention, there is provided amethod of manufacturing a semiconductor device, including: forming athin film containing a predetermined element on a substrate byperforming a cycle a predetermined number of times, the cycle including:forming a first layer containing the predetermined element, nitrogen andcarbon by alternately performing supplying a source gas containing thepredetermined element and a halogen element to the substrate andsupplying a first reactive gas containing three elements including thecarbon, the nitrogen and hydrogen and having a composition wherein anumber of carbon atoms is greater than that of nitrogen atoms to thesubstrate a predetermined number of times; and forming a second layer bysupplying a second reactive gas different from the source gas and thefirst reactive gas to the substrate to modify the first layer.

Here, the phrase “alternately performing supplying a source gas andsupplying a first reactive gas a predetermined number of times” meansthat, when a process of supplying one gas of the source gas and thefirst reactive gas and then a process of supplying the other gas of thesource gas and the first reactive gas are set as one set, both of thecase of performing the set once and the case of performing the set aplurality of times are included. That is, this means that the set isperformed once or more (a predetermined number of times).

The phrase “performing a cycle a predetermined number of times, thecycle including forming a first layer and forming a second layer” meansthat, when the process of forming the first layer and the process offorming the second layer are set as one cycle, both of the case ofperforming the cycle once and the case of performing the cycle aplurality of times are included. That is, this means that the cycle isperformed once or more (a predetermined number of times).

Such expressions in the specification are used with the same meanings asabove.

Supplementary Note 2

In the method of manufacturing a semiconductor device according tosupplementary note 1, it is preferable that the first reactive gascontains a plurality of ligands containing the carbon atoms.

Supplementary Note 3

In the method of manufacturing a semiconductor device according tosupplementary note 1 or 2, it is preferable that the first reactive gascontains three ligands containing the carbon atoms.

Supplementary Note 4

In the method of manufacturing a semiconductor device according tosupplementary note 1 or 2, it is preferable that the first reactive gascontains two ligands containing the carbon atoms.

Supplementary Note 5

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 4, it is preferable that the firstreactive gas includes at least one of amine and organic hydrazine.

Supplementary Note 6

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 4, it is preferable that the firstreactive gas includes at least one amine selected from a groupconsisting of ethylamine, methylamine, propylamine, isopropylamine,butylamine, and isobutylamine.

Supplementary Note 7

In the method of manufacturing a semiconductor device according tosupplementary note 1 or 2, it is preferable that the first reactive gasincludes at least one amine selected from a group consisting oftriethylamine, diethylamine, trimethylamine, dimethylamine,tripropylamine, dipropylamine, triisopropylamine, diisopropylamine,tributyl amine, dibutylamine, triisobutylamine, and diisobutylamine

Supplementary Note 8

In the method of manufacturing a semiconductor device according tosupplementary note 1 or 2, it is preferable that the first reactive gasincludes at least one amine selected from a group consisting ofdiethylamine, dimethylamine, dipropylamine, diisopropylamine,dibutylamine, and diisobutylamine.

Supplementary Note 9

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 8, it is preferable that the firstreactive gas is a silicon-free gas.

Supplementary Note 10

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 8, it is preferable that the firstreactive gas is a silicon-free and metal-free gas.

Supplementary Note 11

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 10, it is preferable that thepredetermined element includes silicon or metal, and the halogen elementincludes chlorine or fluorine.

Supplementary Note 12

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 11, it is preferable that the forming ofthe first layer includes forming the first layer on the substrate whiledischarging the halogen element contained in the source gas and thehydrogen contained in the first reactive gas as a gas.

Supplementary Note 13

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 12, it is preferable that the supplyingof the source gas includes forming an initial layer containing thepredetermined element and the halogen element, and the supplying of thefirst reactive gas includes forming the first layer by reacting theinitial layer with the first reactive gas

Supplementary Note 14

In the method of manufacturing a semiconductor device according tosupplementary note 13, it is preferable that the supplying of the firstreactive gas includes separating at least a part of a ligand or ligandscontained in the first reactive gas from the first reactive gas whiledrawing at least a part of atoms of the halogen element contained in theinitial layer from the initial layer by reacting the initial layer withthe first reactive gas.

Supplementary Note 15

In the method of manufacturing a semiconductor device according tosupplementary note 13 or 14, it is preferable that the supplying of thefirst reactive gas includes combining the nitrogen of the first reactivegas having at least a part of a ligand or ligands being separatedtherefrom with the predetermined element contained in the initial layerby separating at least the part of the ligand or the ligands containedin the first reactive gas from the first reactive gas while drawing atleast a part of atoms of the halogen element contained in the initiallayer from the initial layer by reacting the initial layer with thefirst reactive gas.

Supplementary Note 16

In the method of manufacturing a semiconductor device according tosupplementary notes 13 to 15, it is preferable that the supplying of thefirst reactive gas includes: combining the nitrogen of the firstreactive gas having at least a part of a ligand being separatedtherefrom with the predetermined element contained in the initial layer;and combining the carbon contained in the ligand or the ligands with thepredetermined element contained in the initial layer by separating atleast the part of the ligand or the ligands contained in the firstreactive gas from the first reactive gas while drawing at least a partof atoms of the halogen element contained in the initial layer from theinitial layer by reacting the initial layer with the first reactive gas.

Supplementary Note 17

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 16, it is preferable that the forming ofthe thin film is performed with the substrate being accommodated in aprocess chamber, and an inner pressure of the process chamber when thefirst reactive gas is supplied is set to be higher than that of theprocess chamber when the second reactive gas is supplied, and an innerpressure of the process chamber when the second reactive gas is suppliedis set to be higher than that of the process chamber when the source gasis supplied.

Supplementary Note 18

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 17, it is preferable that the forming ofthe second layer includes forming a layer containing the predeterminedelement, oxygen, carbon and nitrogen (an oxycarbonitride layercontaining the predetermined element), or a layer containing thepredetermined element, oxygen and carbon (an oxycarbide layer containingthe predetermined element) as the second layer by supplying anoxygen-containing gas as the second reactive gas to the substrate, andthe forming of the thin film includes forming a film containing thepredetermined element, oxygen, carbon and nitrogen (an oxycarbonitridefilm containing the predetermined element), or a film containing thepredetermined element, oxygen and carbon (an oxycarbide film containingthe predetermined element) as the thin film.

Supplementary Note 19

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 17, it is preferable that the forming ofthe second layer includes forming a layer containing the predeterminedelement, the carbon and the nitrogen (a carbonitride layer containingthe predetermined element) as the second layer by supplying anitrogen-containing gas as the second reactive gas to the substrate, andthe forming of the thin film includes forming a film containing thepredetermined element, carbon and nitrogen (a carbonitride filmcontaining the predetermined element) as the thin film.

Supplementary Note 20

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 17, it is preferable that the forming ofthe second layer includes forming a layer containing the predeterminedelement, oxygen, carbon and nitrogen (an oxycarbonitride layercontaining the predetermined element) as the second layer by supplying anitrogen-containing gas and an oxygen-containing gas as the secondreactive gas to the substrate, and the forming of the thin film includesforming a film containing the predetermined element, oxygen, carbon andnitrogen (an oxycarbonitride film containing the predetermined element)as the thin film.

Supplementary Note 21

In the method of manufacturing a semiconductor device according to anyone of supplementary notes 1 to 17, it is preferable that the forming ofthe second layer includes forming a layer containing the predeterminedelement, oxygen, carbon and nitrogen (an oxycarbonitride layercontaining the predetermined element) as the second layer by supplying anitrogen-containing gas as the second reactive gas to the substrate andthen supplying an oxygen-containing gas as the second reactive gas tothe substrate, and the forming of the thin film includes forming a filmcontaining the predetermined element, oxygen, carbon and nitrogen (anoxycarbonitride film containing the predetermined element) as the thinfilm.

Supplementary Note 22

According to another aspect of the present invention, there is provideda method of manufacturing a semiconductor device, including: forming athin film by stacking a first layer and a second layer on a substrate byperforming a cycle a predetermined number of times, the cycle including:forming the first layer containing the predetermined element, nitrogenand carbon by alternately performing supplying a source gas containingthe predetermined element and a halogen element to the substrate andsupplying a first reactive gas containing three elements including thecarbon, the nitrogen and hydrogen and having a composition wherein anumber of carbon atoms is greater than that of nitrogen atoms to thesubstrate a predetermined number of times; and forming the second layercontaining the predetermined element by alternately performing supplyingthe source gas to the substrate and supplying a second reactive gasdifferent from the source gas and the first reactive gas to thesubstrate.

Supplementary Note 23

In the method of manufacturing a semiconductor device according tosupplementary note 22, it is preferable that the forming of the secondlayer includes forming a layer containing the predetermined element andthe nitrogen (a nitride layer containing the predetermined element) asthe second layer by supplying a nitrogen-containing gas as the secondreactive gas to the substrate, and the forming of the thin film includesforming a film containing the predetermined element, the carbon and thenitrogen (a carbonitride film containing the predetermined element)formed by alternately depositing the first layer and the second layer asthe thin film.

Supplementary Note 24

In the method of manufacturing a semiconductor device according tosupplementary note 22, it is preferable that the forming of the secondlayer includes forming a layer containing the predetermined element andoxygen (an oxide layer containing the predetermined element) as thesecond layer by supplying an oxygen-containing gas as the secondreactive gas to the substrate, and the forming of the thin film includesforming a film containing the predetermined element, the oxygen, thecarbon and the nitrogen (an oxycarbonitride film containing thepredetermined element) formed by alternately depositing the first layerand the second layer as the thin film.

Supplementary Note 25

According to still another aspect of the present invention, there isprovided a method of manufacturing a semiconductor device, including:forming a thin film containing a predetermined element on a substrate byalternately performing the following steps a predetermined number oftimes: forming a first layer containing the predetermined element,nitrogen and carbon by supplying a source gas containing thepredetermined element and a halogen element, and a first reactive gascontaining three elements including the carbon, the nitrogen andhydrogen and having a composition wherein a number of carbon atoms isgreater than that of nitrogen atoms to the substrate; and forming asecond layer by supplying a second reactive gas different from thesource gas and the first reactive gas to the substrate to modify thefirst layer.

Supplementary Note 26

According to yet another aspect of the present invention, there isprovided a method of processing a substrate, including: forming a thinfilm containing a predetermined element on a substrate by performing acycle a predetermined number of times, the cycle including: forming afirst layer containing the predetermined element, nitrogen and carbon byalternately performing supplying a source gas containing thepredetermined element and a halogen element to the substrate andsupplying a first reactive gas containing three elements including thecarbon, the nitrogen and hydrogen and having a composition wherein anumber of carbon atoms is greater than that of nitrogen atoms to thesubstrate a predetermined number of times; and forming a second layer bysupplying a second reactive gas different from the source gas and thefirst reactive gas to the substrate to modify the first layer.

Supplementary Note 27

According to yet another aspect of the present invention, there isprovided a substrate processing apparatus including: a process chamberconfigured to accommodate a substrate; a source gas supply systemconfigured to supply a source gas containing a predetermined element anda halogen element into the process chamber; a first reactive gas supplysystem configured to supply a first reactive gas containing threeelements including carbon, nitrogen and hydrogen and having acomposition wherein a number of carbon atoms is greater than that ofnitrogen atoms into the process chamber; a second reactive gas supplysystem configured to supply a second reactive gas different from thesource gas and the first reactive gas into the process chamber; and acontrol unit configured to control the source gas supply system, thefirst reactive gas supply system and the second reactive gas supplysystem so as to form a thin film containing the predetermined element onthe substrate, by performing a cycle a predetermined number of times,the cycle including: forming a first layer containing the predeterminedelement, the nitrogen and the carbon by alternately performing supplyingthe source gas to the substrate in the process chamber and supplying thefirst reactive gas to the substrate in the process chamber apredetermined number of times; and forming a second layer by supplyingthe second reactive gas to the substrate in the process chamber tomodify the first layer.

Supplementary Note 28

According to yet another aspect of the present invention, there isprovided a program that causes a computer to perform a process offorming a thin film containing a predetermined element on a substrate ina process chamber by performing a cycle a predetermined number of times,the cycle including: a process of forming a first layer containing thepredetermined element, nitrogen and carbon by alternately performingsupplying a source gas containing the predetermined element and ahalogen element to the substrate in the process chamber and supplying afirst reactive gas containing three elements including the carbon, thenitrogen and hydrogen and having a composition wherein a number ofcarbon atoms is greater than that of nitrogen atoms to the substrate inthe process chamber a predetermined number of times; and a process offorming a second layer by supplying a second reactive gas different fromthe source gas and the first reactive gas to the substrate in theprocess chamber to modify the first layer.

Supplementary Note 29

According to yet another aspect of the present invention, there isprovided a non-transitory computer-readable recording medium storing aprogram that causes a computer to perform a process of forming a thinfilm containing a predetermined element on a substrate in a processchamber by performing a cycle a predetermined number of times, the cycleincluding: a process of forming a first layer containing thepredetermined element, nitrogen and carbon by alternately performingsupplying a source gas containing the predetermined element and ahalogen element to the substrate in the process chamber and supplying afirst reactive gas containing three elements including the carbon, thenitrogen and hydrogen and having a composition wherein a number ofcarbon atoms is greater than that of nitrogen atoms to the substrate inthe process chamber a predetermined number of times; and a process offorming a second layer by supplying a second reactive gas different fromthe source gas and the first reactive gas to the substrate in theprocess chamber to modify the first layer.

What is claimed is:
 1. A method of manufacturing a semiconductor device,comprising: forming a film containing a predetermined element, oxygen,carbon and nitrogen on a substrate in a process chamber by performing acycle a predetermined number of times, the cycle includingnon-simultaneously performing: (a) supplying a source gas containing thepredetermined element and a halogen element to the substrate in theprocess chamber; (b) supplying a first reactive gas containing carbon,nitrogen and hydrogen to the substrate in the process chamber whereinnumber of carbon atoms in each molecule of the first reactive gas isgreater than that of nitrogen atoms in each molecule of the firstreactive gas; and (c) supplying an oxidizing gas as a second reactivegas to the substrate in the process chamber, wherein an inner pressureof the process chamber in (b) is greater than that of the processchamber in (a), and the cycle further includes: (d) supplying anitriding gas as a third reactive gas to the substrate.
 2. The methodaccording to claim 1, wherein the first reactive gas comprises at leastone selected from the group consisting of amine and organic hydrazine.3. The method according to claim 1, wherein the first reactive gascomprises at least one amine selected from the group consisting ofethylamine, methylamine, propylamine, isopropylamine, butylamine, andisobutylamine.
 4. The method according to claim 1, wherein the firstreactive gas contains a plurality of ligands containing the carbonatoms.
 5. The method according to claim 1, wherein the first reactivegas is a silicon-free and metal-free gas.
 6. The method according toclaim 1, wherein the first reactive gas is a silicon-free gas.
 7. Themethod according to claim 2, wherein the second reactive gas comprisesat least one selected from the group consisting of NH₃ gas, N₂H₂ gas,N₂H₄ gas and N₃H₈ gas.
 8. The method according to claim 3, wherein thethird reactive gas comprises at least one selected from the groupconsisting of O₂ gas, N₂O gas, NO gas, NO₂ gas, O₃ gas, H₂ gas+O₂ gas,H₂ gas+O₃ gas, H₂O gas, CO gas and CO₂ gas.
 9. The method according toclaim 1, wherein the predetermined element comprises silicon or a metal,and the halogen element comprises chlorine or fluorine.
 10. The methodaccording to claim 1, wherein each of the first reactive gas, the secondreactive gas, and the third reactive gas is thermally activated undernon-plasma condition and supplied to the substrate.
 11. A method ofmanufacturing a semiconductor device, comprising: forming a filmcontaining silicon, oxygen, carbon and nitrogen on a substrate in aprocess chamber by performing a cycle a predetermined number of times,the cycle including non-simultaneously performing: (a) supplying asource gas containing silicon and a halogen element to the substrate inthe process chamber; (b) supplying a first reactive gas containingcarbon, nitrogen and hydrogen to the substrate in the process chamberwherein number of carbon atoms in each molecule of the first reactivegas is greater than that of nitrogen atoms in each molecule of the firstreactive gas; and (c) supplying an oxidizing gas as a second reactivegas to the substrate in the process chamber, wherein an inner pressureof the process chamber in (b) is greater than that of the processchamber in (a), and the cycle further includes: (d) supplying anitriding gas as a third reactive gas to the substrate.
 12. A method ofmanufacturing a semiconductor device, comprising: forming a filmcontaining a metal element, oxygen, carbon and nitrogen on a substratein a process chamber by performing a cycle a predetermined number oftimes, the cycle including non-simultaneously performing: (a) supplyinga source gas containing the metal element and a halogen element to thesubstrate in the process chamber; (b) supplying a first reactive gascontaining carbon, nitrogen and hydrogen to the substrate in the processchamber wherein number of carbon atoms in each molecule of the firstreactive gas is greater than that of nitrogen atoms in each molecule ofthe first reactive gas; and (c) supplying an oxidizing gas as a secondreactive gas to the substrate in the process chamber, wherein an innerpressure of the process chamber in (b) is greater than that of theprocess chamber in (a), and the cycle further includes: (d) supplying anitriding gas as a third reactive gas to the substrate.